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Unrevealed Truths (The Coronation of the High Hierophant)

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“All I know of tomorrow is that Providence will rise before the sun.” — Henri-Dominique Lacordaire

 

A thousand questions hammered in the Doctor’s mind while a disapproving priestess dressed his wounds. Or perhaps the pounding was the after-effect of a sharp blow to the head.

He could not recall precisely how he had arrived in this cell. There were two guards and no doors, a logical precaution in a place with reconfigurable walls and transmat navigation. While the Doctor had been unconscious, someone had relieved him of his transmat key along with his coat, cricket ball, and everything else in his pockets. Not to mention his shirt and jumper. That left him with only his wits and whatever he could jury-rig out of  a medical stabiliser. The priestess was busy attaching one to the bandages around his midsection. He wished he could ask her for tidings of Nyssa, but Achille’s warning had gagged him quite effectively.

She was out of imminent danger, at any rate— or was she?

The Doctor’s worst fears had proved misplaced. Achille had not coerced Nyssa into providing him with an heir. Instead, the risk of childbirth was his, not hers, and the Doctor had endangered him with yet another abduction when he was in a vulnerable state. Logically, it should not cause any complications. If a transmat was miscalibrated badly enough to disrupt the birthing process, it would also impair bodily functions like circulation and neurotransmission. But it was not the sort of thing one should put to the test.

And that was quite apart from the challenges of medical care in a culture that denied Achille’s very existence. Unless Nyssa had studied multisex obstetrics on Traken, he had no specialists to call upon should anything go wrong, nor even to know what was normal. A pity the Celestenes had latched onto the symbolism of Apollo instead of Zeus, who, predatory habits notwithstanding, did offer an archetype of male birth.

The Doctor sympathised with Achille, but he seemed to be bearing up well. Nor did his predicament change the fact that, as far as history was concerned, Nyssa would not survive the night. The record of how she died was a lie, but to cover what truth? There were two possibilities. One, Achille’s words had been a threat, not simply a warning. She might be a hostage. The sham marriage need last only until the child was born, and then the “mother” would be dispensable— a liability, even. That would certainly explain her encoded plea. Yet it did not fit Achille’s profile, if he really was the pampered but kindhearted young prince that Jo had befriended. Which meant Nyssa might be a willing party in this subterfuge. But in that case, why the distress calls? More to the point, where was she? Surely she ought to be helping with the birth?

Racking his memory for everyone he had encountered while infiltrating the royal apartments, the Doctor finally remembered the overdressed figure of the Hierophant who had tried to bar his way.

“Oh, Nyssa.” He had not meant to say it aloud.

“Here, that’s quite enough from you!” said the guard, hand dropping to his sword-hilt. “Speak of Her Divine Grace with more respect! She bears the new Apollo this night!”

“I meant no disrespect,” the Doctor said. “I brought her here, remember? She’s an old friend. You might consider that there’s other ways to value your queen than as breeding stock.”

“You dare—”

“Is that comfortable?” the priestess interrupted, checking the medipatch’s indicator lights.

“Er… yes, thank you,” he said. “I don’t suppose you could pass a message to the Queen for me?”

“Young man,” she said, clearing away bandage wrappers and bottles of ointment, “don’t you think you’ve bedeviled Her Grace enough for one night?”

“Very probably,” he said, irked at himself for forgetting the pantomime. “My apologies.”

“You can save those for when you’re released. Which may not be for some while, Jupiter willing.” She nodded to the guards. “That should do.”

“Thank you, Sister,” one said. He unsnapped the palm of his gauntlet and held it up. “I’ll see you out. Destination?”

“Hygieia’s Terrace, if you please.”

“Wait! Tell Rhea—”

They were gone. The Doctor began to examine the seamless walls of the small chamber under the glare of the remaining guard. But there was not much he could do, so long as he was trapped in a sealed room under close supervision. Before long, the healer’s escort returned and drew his sword.

“Your turn,” he said. “And no more trouble from you. They’re watching. Raise your hand.”

“I must see Sir Adyton at once,” the Doctor tried again, hands firmly in his pockets. “There’s someone who means the Queen harm, but it’s not I. The Warder knows I would only act in her best interests.”

“That’s not what we heard—” the other began hotly.

“Sir Adyton, eh?” The first man gave a humourless grin. “Aye, those are my very orders. You’ll see him.”

“Why do I have a feeling there’s a catch?” the Doctor said. But it was the only way out of this doorless chamber. “Very well. Take me to him.” He strode forward and grasped his hand.

The slight twinge of displacement told the Doctor he had moved, even if the only visible sign was the disappearance of the other guard. His surroundings seemed unchanged. The milk-white cell was exactly the same size, with bunk, commode and sink in the same configuration. The guard released his hand and rapped sharply on the nearest wall, which took on a translucent sheen.

“If he’s of a mind to answer, you’ll see him,” he said with a smirk. “Enjoy your stay.”

“That would be easier if I knew for certain that Nyssa was all right.” The guard snorted and vanished. The Doctor began to prowl the cell and inspect the meagre facilities. Halfway around the room, a dour grumble cut across the silence.

“Well? What have you to say?” It was Adyton, slightly muffled. “And what infraction brings you here?”

“Don’t you know, Warder?” He turned and saw the translucent wall had become transparent. The Warder stood on the other side, arms folded, expression stern, stature somewhat diminished. It took the Doctor a moment to figure out why. He was out of uniform, clad only in tunic, leggings, and a leather shirt bearing the imprint of missing armour. Many lines of care had stitched themselves over his brows and alongside his frown since last they had spoken. “Come to that, what are you doing here?”

“Awaiting trial,” Adyton said. “My hands are stained with royal blood, shed in defence of one who bears the King’s heir.”

“Ah. Of course.” The Doctor nodded. If anyone knew the High Hierophant’s secret, it would be his former bodyguard. “Well, then, I’m rather afraid I tried to take the Queen to an offworld medical facility. Out of concern for her safety, you understand. En route back to my ship I learned… that such assistance was unnecessary. The labour was going along splendidly, so far as I could make out.”

The Warder stood rigid until the last statement, then he relaxed. He searched the Doctor’s face for a long moment before muttering, “For your sake, you had better hope so.” He began to pace. “Did His Majesty send any word, any instruction?”

“There wasn’t time. But I overheard something while I was looking for the royal apartments. An energy weapon has been stolen from your Vault. Your people assumed I’d taken it. I didn’t. I don’t suppose the Queen’s attacker had inside help?”

Adyton stiffened. Then he slammed a hand against the forcefield, reeling back from the jolt of a security barrier that sparked under his fist. He struck again. And again.

The Doctor winced. “I’m terribly sorry to be the bearer of bad news, but that’s really not going to help. We’ve simply got to get out of here.”

There was a crackle of static. “Sir? What’s the Lord Doctor doing?”

“Nothing,” Adyton said, massaging his hand and turning angrily to address the air. “But you should have told me that offworlder weapon had been stolen.”

“I’m sorry, sir, but you’ve been relieved of duty by your own command.”

“That was before I realised Auguste’s accomplice might try to avenge him.” He took a deep breath. “I cannot order, but I implore you to double and treble the guard on the royal apartments. Send word to His All-Holiness that the serpent we feared may yet bear one tooth, and that Their Majesties are in jeopardy. Quickly, man! There is no time to lose.”

“Aye, sir. We’ll see to it.”

Adyton opened and closed his hands, striding in and out of view in frustration. “This cannot be countenanced. Where were you, Lord Doctor, during all the moons that we tried to track this serpent?” he said. “I know its name. But we could never prove our suspicions. If he strikes now, while thou and I are shackled here—”

“He’ll try,” the Doctor said, mind racing. “I hope that’s not the real reason for…” He hesitated, guessing that this conversation was not private. “Listen. Your chronicles say that the child lives, but Nyssa dies tonight. My own people’s laws forbid me from interfering with history. But I can’t let that happen. Do you understand? I have to reach her before that future becomes fact.”

“You would kill to save her?”

“I’d prefer to find some other way, but—”

There was another crackle of static. “Thank you, Sir Adyton. That’s cleared up the motive. We have the Doctor’s confession.”

“Confession?” The Doctor blinked.

“They think you meant to slay the child to save the Queen.”

“I meant nothing of the sort!”

“Chariklo, Lord Doctor. If ever you found yourself in need of safe passage, Her Serene Grace bade me tell you to remember, log Charik—”

There was a pop, and the wall between them abruptly went opaque. The Doctor slammed his fist against it. He received a powerful electric shock. Drawing a breath, he tapped three times as the guard had done when they arrived.

“Come on!” he fumed. “We weren’t finished! We’re trying to save your precious Hierophant’s life!”

There was no response.

How long had he been knocked out? How long since that weapon had been stolen? Were the precautions Sir Adyton had ordered enough?

“Think, Doctor. Think.

Chariklo. The place where he had come nearest to losing Nyssa. He could see her clearly in his mind’s eye, a spacesuit-clad figure slowly spinning high above his head in the blackness of space. Log Chariklo. It sounded like some sort of password, but to what?

10199 Chariklo, to use its proper designation. He groaned. Of course. The log of 10199. Didn’t she remember how much he hated logarithms? Well, it was a puzzle to solve, and he needed to steady his thoughts. Still fuming, he sat down on the bunk. The medical sensor beeped as he moved. Angrily, he peeled it off and began to flex its edges with slight, rapid movements as he focused his mind on maths.

log 10199 = log 104 + log (1.0199) = 4 + log (1.0199)…

Somewhere around the seventh decimal place, he found the backing of the medical patch was beginning to come loose. Slowly, carefully, pretending not to look at it, he continued working the warm plastic until the layers of the device split apart like the pages of a book. He glanced down. The nano-circuitry was suspended in sheets of clear film far too delicate to be tampered with by hand. But something glinted in one corner of the casing.

Another guard materialised in front of him, hand on sword-hilt. “I’ll take that, m’lord,” he snapped, holding out his hand.

“What? Oh. Take it. I don’t need it.” He patted the bandage around his ribs. “All healed.” Not quite, but it hardly mattered now. “I don’t suppose you could return my shirt and coat? I feel distinctly underdressed. It would be dreadfully embarrassing if the High Hierophant summoned me for an audience.”

Expressionless, the guard plucked the medical patch from him and vanished.

The Doctor squinted at the small item he had tucked between his fingers while handing the sensor across. A jewel. Smaller than the ornate key-jewels worn on necklaces, but he knew at once what it was for. At last, Nyssa had thrown him a line. He pressed it between forefinger and thumb and held it tight, barely daring to breathe. After six seconds, he thought to himself, Home.

Nothing happened.

A password. It needed a special code to bypass the security lockouts. With a renewed sense of purpose, he began working on the next digit. Time was running out.

He had it. Closing his eyes and clearing his mind, he focused on each digit in turn. 4.00855758178. There was a tingle of warmth against his hand.

Nyssa, he thought fiercely. Take me to Nyssa.


The cell vanished. With the bunk gone, he fell in an undignified heap on the floor, nearly losing hold of the small gem. Hurriedly he slipped it in his pocket and looked around.

He had returned to the same chamber where he left Achille who knows how many hours ago. But it was much changed. Flowers filled the troughs around the room. Soft music was playing. The TARDIS was bedecked in garlands. In fact, the ceiling above it was shimmering and warping slightly; the TARDIS shell was causing local interference with the forcefields. Just as well that the floor was made of real stone and tile, anchored to the scaffolding of the tower.

The room was cold and silent. The quivering expectancy of the Lattice bore down on his mind like the pregnant silence after a flash of distant lightning, just before the thunder. The general anticipation amplified his own, for all he tried to block it out.

“Your Majesty?” he called, hardly daring to hope.

Two guards shouted from the balcony, one from across the room. They pelted towards him, drawing their swords as they came. Despair crashed over him. He was back to square one, and there was no more time.

At his left, a shimmer: the door in the wall perpendicular to the balcony had turned translucent. The gold-clad figure he had seen before stepped out and waved an imperious hand. “Remain at your posts. The Doctor has obeyed our royal summons to attend Her Serene Grace. He will give us no further trouble.”

“All-Holiness?” The guards saluted, but did not withdraw.

“Your Divine Grace, we have it from his own lips that he will stop at nothing to preserve the offworlder Queen. Nothing.

“I apprehend. Well, Doctor?”

He bowed deeply and forced himself not to stare. “I came for her sake. But I assure you, I can’t rate her life above another’s, no matter how fond I am of a friend.”

“A proper sentiment. Captain, I commend your concern, but turning away the Queen’s physicker would entail greater risk. He shall answer to me and to my blade. Resume your posts. Corporal, please join them outside.”

“Sire.” They saluted again, obeying with visible reluctance. There was another tantalising silence while they filed out.

“Nyssa?” he whispered.

The instant they were out of sight, she threw her arms around him, knocking the mask askew. A voice that was not quite hers and not quite Achille’s crackled against his chest. “You do choose your moments, don’t you?”

“Shh. Careful.” Acutely aware of eavesdroppers, he reached down and resettled the voice modulator over her mouth, wishing nothing more than to tear away the mask and take a good look at her. Even her eyes had been transfigured, grey-green refracted to hazel by contacts or Rayleigh scattering. Her tight curls had loosened to a Byronic cascade, and, to his amused indignation, she was sporting a false beard nearly as foolish as the Master’s weak goatee. He wanted to laugh, or shout, or shake her, or tell her how desperately glad he was to see her. Instead, all he said was, “I can’t believe you’re a party to this charade. Don’t you realise what you’re doing is appallingly dangerous?”

“Don’t you think I’m aware of that? There have been three assassination attempts since you left.” Her disguised voice made it difficult to register that he had truly found her— alive, she’s alive— and that he was not too late. “Where were you? I was afraid I’d have to smuggle myself off-planet.”

“I’m sorry. I thought… well it doesn’t matter what I thought. What matters is you’ve trapped yourself in a temporal nexus. We have to extricate you somehow without altering history. As far as the official records are concerned, you died tonight.”

“I know, I—” She stopped, catching something in his tone. “You knew that, and you still came back for me?”

“Yes.” He smiled weakly. “You won’t tell the Time Lords, will you?”

“Oh, Doctor.” She hugged him again, fiercely. “I’m sorry, too. It never occurred to me you’d stumble across our cover story. Thank you.”

“Is there any reason not to go at once?” He knew the answer as he said it.

She glanced over her shoulder. “We have to play this through. Otherwise, as you say, history won’t know what to make of my departure. Anyway, I can’t leave Achille yet. He’s just getting to the hardest part. Do you mind? If you’d prefer to wait in the TARDIS—”

“I’ll assist, if I may,” he said. “After all, I’m the Queen’s personal physician.”

Her moon-smile under the lip of the mask should have fooled no one, beard or no beard. “That will greatly relieve her mind, I’m sure.”

She led the way into the adjacent room, the one which would have been hers if she had remained in their suite that fateful night. It, too, was ornamented with fresh flowers, shell-lanterns, and scattered furnishings that were more decorative than practical. The large bed had been pushed against the far wall. Piped-in music provided an exalted ambiance, or would have done, if not for a stream of expletives so colourful that the TARDIS refused to translate them. Against that profane background, the soaring strains of Lully’s Te Deum seemed somewhat incongruous.

Nyssa shook her head with a smile and led the way towards the trio gathered under a makeshift arbour assembled from embroidered tapestries, garlands, and several of those spindle-shaped sculptures.

“An intriguing metaphor, but anatomically unlikely, Your Highness,” the Doctor said, following her. “Good evening, Majesty, Your Grace.”

“Well met again, my lord.” Achille bared a strained grin. “You find me somewhat… out of sorts. But we are right pleased to see you.”

He was standing just as before, garbed in a loose green robe with his arms draped over the shoulders of the elderly midwife, who bore his weight stoically, and his mother, leaning heavily on a staff she had not needed when the Doctor last saw her.

“Allow me, Your Grace,” the Doctor said, moving to relieve Rhea. The Dowager sank with a grateful nod into a nearby bergère. “I’m curious why a culture so well-versed in gravitic engineering doesn’t employ a suspension field for this sort of thing.”

“Tradition,” Nyssa said, taking over from the midwife. “Nobles are born upstanding. Here, Lucina, I’ve brought you an assistant.”

“Looks to me like you’ve brought a man,” the old woman grumbled, “as if we didn’t have sacrilege already with you two children all topsy-turvy.”

“That being so, one more sacrilege shall make no difference,” Achille said, eyes dancing with a hint of his usual bravura. “And, Doctor, let it not be said a king failed to match a queen in feats of hardihood.” Then he grimaced, gripping the Doctor more tightly as a contraction seized him.

“Don’t forget to breathe,” Nyssa reminded him. “Deep breath in, deep breath out. Slow and stately, Entreé Grave.”

“I feel more like… l’éléphant grave,” he said, when he could speak again. “Doctor, how do you bear it? Changing bodies, I mean. Being trapped in a form not your own.”

“Well,” said the Doctor, “the last time, I had excellent help.” He tipped his head towards Nyssa.

“As have we. You have our thanks, Lord Doctor, even if you did try to deprive us of her at a most inconvenient hour,” Rhea said. “That was a reckless strategem, my lord, even for you.”

“Quite in character, I should’ve called it,” Nyssa said.

“Thank you, Nyssa,” he said testily. “Your Grace, if I may, I’d like to offer my condolences. I’m so sorry about...”

“It is not meet to speak of it now,” Rhea said, voice remote. “But while a mother’s heart grieves, I give thanks that my grandchild will not be born under a Sword of Damocles.”

“I’m afraid that may be a little premature,” he said. “Someone’s stolen that energy weapon that Auguste used during the Coronation Feast, and I think they’re still at large.”

“We’ve heard,” Nyssa said. “That’s why I suggested Achille remain here. The court believes we’re in the royal apartments. Besides,” she added apologetically, “the TARDIS is here, as a last resort. You left the door unlocked.”

He frowned. “I hope you’ve had these chambers sealed off?”

“All that can be done has been done,” Rhea said. “The Hierophant’s key has the only access code.” With those words, the whole room quaked. Achille let out a low groan.

Nyssa stroked his face soothingly. “The Lattice moves with you.”

“No. Floor… rock solid,” he said, panting through another contraction. “Doctor, check… outside.”

“By all means. Excuse me, Majesties.” The Doctor transferred Achille’s weight to one of the spindle-shaped sculptures. Lucina, who had been checking his progress, slipped under his arm muttering something about so-called doctors and their help.

The Doctor made for the door. Halfway across the room, he heard footsteps clacking behind him. He felt a surge of elation and dread. Even with her ostentatious footwear, it was a simple joy to hear Nyssa hurrying to catch up to his long stride, just like the old days. But it was also a risk, one he refused to permit until safely away from this planet. “Stay with him, Nyssa.”

“Doctor—”

The door exploded in a bubble of searing light. He threw up his arms, shielding his face from the blast. A shockwave lifted him up by the elbows and hurled him backwards. Vases shattered. Petals scattered, stripped from stems like chaff in a hurricane. The bed slewed sideways. For a split second, the ceiling and part of the walls surrounding the door disappeared. An armoire crashed down from the room above, narrowly missing him as it struck the floor and splintered.

Lying on his back, the Doctor saw a tall man in dark burgundy come striding through the gaping hole before the Basilica’s structure reasserted itself. Acheron glanced down at him with a contemptuous scowl. Almost casually, he lowered his arm, bringing the weapon down to aim at his head.

“That’s… not the sort of thing… to wave about… complex gravitational fields,” the Doctor stammered. Even if he weren’t stunned, he had little chance of rising up to knock the weapon out of the man’s hand. The Celestenes might not be very practiced with firearms, but at such close range, Acheron could hardly miss.

“How dare you, Uncle?” There was a ring of sliding metal. It seemed Nyssa had been far enough back to escape the shockwave, or else the Doctor had shielded her from the brunt of it. But the sword bridging the air above him was no match for a pulse laser. “Begone! You have no place here!”

“Nor does this offworlder. Yet you, truly, belong in women’s province.” Acheron’s laugh was harsh. “You may bar the birds of heaven from the Celestial Basilica, but the blade of truth cuts through all lies!”

The Doctor breathed easier when he dropped the laser into his belled sleeve and reached for his sword-hilt, suiting gesture to taunt. Focused beam energy in a network of artificial gravity fields was rather like a lit match in an oil refinery. Swords, on the other hand, were unlikely to kill more than one person at a time. Not that it was very comfortable being that person.

“Stop!” The Hierophant’s sword was already poised with the point hovering over the man’s breastbone.

“Well?” Acheron said, and gave a barking laugh. “You have no stomach for manly deeds. Whereas I will do what needs to be done!”

The Doctor rolled, sweeping his feet to cut the man’s legs out from under him. “Stay back!” he told Nyssa, planting a knee and pushing off to grab Acheron’s elbow, using it to pull himself up. His opponent staggered. The Doctor wrenched his sword-arm behind his back. “Now then,” he said, “Let’s just step into the next room, shall we, and discuss this matter like civilised men.” His prisoner snorted. “I hear your family tree is quite pruned enough already.”

A guttural cry— high, but not a woman’s voice— ended in a choking cough. Achille must be trying to keep silent. Acheron turned towards the sound. Nyssa jabbed at his mask, drawing his eyes back to her. “Ballroom, Doctor,” she said urgently.

“Phaugh!” Heaving against the Doctor’s grip, Acheron reached out and caught her wrist, twisting it with a violent jerk. “La belle danse will not save you from the people’s wrath when I tear the mask of deception away from you… like so!” The sword flew from her grasp.

The Doctor lunged, snaring the jewelled hilt as it spun past.

“Now!” she said.

“No, wait!” In catching the sword, he had lost hold of her assailant. His swipe for the man’s shoulder found only air. They were gone. A distant alarm began to sound.

Painfully aware of the empty space where she had been standing just a moment ago, he remembered Nyssa’s leap of faith, tumbling backwards over the balcony and trusting that he would catch her. He must not fail this time. Fumbling for the jewel in his pocket, he projected the thought: Ballroom.

Nothing happened.

He peered down in consternation at the jewel pinched between his fingers.

Rhea, who had been trying to conceal her son with her voluminous robes, called to him urgently. “Doctor, make haste! We cannot risk her being discovered.”

“I know!” he said. “The transmat’s not responding!”

“Heavenly Gates!” Achille said, fighting to get the words out. “Duplicate… royal keys… detected. Lockdown.”

Rhea started towards a panel on the wall. “I shall contact the Guardians of the Heavenly Gates to unlock the King’s key, but there is no time—”

“Don’t bother,” the Doctor said. “My ship’s faster.” He was already moving. On the far side of the door, he nearly tripped over one of the guards blocking the threshold in the next room. The other two lay outside, one of them crushed under an aircar whose nose had come to rest embedded in the balustrade, its engines straining to keep it aloft. Of course: the easiest way to bypass transmat security protocols was to avoid them altogether.

The TARDIS door opened at his touch. He dashed inside, tossed the Hierophant’s sword into the umbrella stand, and threw himself at the controls. Once again, the TARDIS felt sluggish, a hazard light blinking under his hands as he brought the ship to an abrupt stop.

“Sorry, old girl. I’m having one of those days too.” Snatching up the sword, he bolted outside.


The translucent floor was glowing ominously around the base of the TARDIS. His ship had landed in a depression— no, the gravitational fields were struggling to bear its mass. As he stepped out, the dance floor began to divide into circular zones, each circle rising to a peak like a carousel’s roof and beginning to turn. Just as before, the smaller gyres orbited the ballroom’s central pylon like planets around a star. With no dancers or music to give life to stark geometry, it was an eerie sight. The only sounds were the muffled whoosh of the waterfall suspended overhead and the unlovely clash of metal striking metal.

The Doctor raised his head and charged towards the sounds of battle. To his relief, he saw that Nyssa was not alone. Some of the ballroom guards had come to her aid. Two had already fallen. Murder and violence, in a place where both were almost unheard-of: the Doctor thought of Traken. The remaining two guards were sparring furiously with the ex-Regent near the centre where the floor was rising to form a plateau above the rest.

A pity the transmat had failed to relieve Acheron of his weapons. But why was Nyssa not using the guards’ cover to escape? His pace quickened when he spotted the reason. She was clinging to the gun in Acheron’s left hand, trying to spoil his aim while he fended off his attackers with consummate swordsmanship. If she let go, he could fire at her point blank.

As the Doctor bounded up the stepped slope, another guard was cut down. Acheron turned upon Nyssa and yanked the weapon out of her hands. It went off. An umbrella of white light burst overhead with a tremendous explosion. The Doctor looked up in amazed horror to see the translucent roof splash outwards and vanish. The upper cladding of the pylon was blasted loose by the shockwave. Fragments rained down, the largest landing across the moon-bridge and barring the path of more guards charging into the hall. The waterfall, which had formed a canopy over the roof’s dome, came sluicing down in a torrent, setting off sparks where it struck the pylon’s exposed infrastructure. Nyssa’s last defender was carried away by the current. She nearly slid after him, but Acheron seized her collar, dragging her back. The Doctor fought his way up to them through the spray.

“Release him!” he said. “For goodness’ sake, man, he’s your sister’s son!”

“Son?” Acheron laid the sword across her neck. Nyssa stopped struggling. The Doctor froze. Meeting his eyes with a gloating smile, Acheron brought it up slowly and deliberately to slice the false beard away. “A eunuch, rather, who would bequeath Apollo’s crown to a harlot’s spawn with God knows what father! Is the babe yours, Lord Doctor? Can you even be sure? Phaugh! It sickens me to touch this unnatural freak.”

“Let him go,” the Doctor said. Force was no use, especially while Acheron held Nyssa’s life in his hands. “You’re wrong. The child is Achille’s, beyond a shadow of doubt.” Nyssa gave him a warning look, but he pressed on. He had the advantage of foreknowledge. A girl would face obstacles down the road, but at least there was little chance of a Y chromosome pointing to a different father. “A blood test should prove its paternity.”

“Paternity?” Acheron sneered. “Then Hygieia’s physickers have truly outdone themselves. Perhaps the miracle child does indeed carry the blood royal, but this— this— perversion of nature— need not blaspheme the Celestial Basilica any longer. No more pretender! I shall silence her lies— so!”

“NO!” The Doctor threw himself at Acheron, but there was absolutely nothing he could do. There was a grating metallic crack. Time seemed to miss a beat. But Nyssa had defended herself in the only way she could, tucking her chin down at the last second. Instead of her throat, the sword sliced across the mask and split its metal face on the diagonal. Drops of blood flew, but not so much that the Doctor feared for her life. Enraged, he pressed his attack. Acheron let slip his victim to meet the furious onslaught.

“Go, Your Majesty!” the Doctor urged. Keeping half an eye on her, he was nearly disarmed when Acheron used a sudden devious twist.

Nyssa edged away, the lower half of the mask dangling from the wires of the now-useless voice modulator, blood trickling down her cheek. “Be careful!” she hissed, the whisper disguising her voice. He caught a glimpse of her worried eyes as she turned and fled. Acheron aimed a slice at her retreating back that he barely managed to deflect.

Then she was safely out of reach. The terrible moment had been averted. With a rush of adrenalin and singing relief, he focused his attention fully on swordplay. He needed it. Acheron was a formidable opponent. The Doctor was grateful he had a younger body than the last time he had come here. Even his third incarnation would have been hard-pressed to match the ex-Regent blow for blow.

“You’re a fine swordsman,” Acheron said grudgingly. “Had you wed the princess before she mutilated herself with her mother’s connivance, we might have had a worthy king.”

“Sorry, not really my line of work,” the Doctor said. “Look, why don’t you just give up? You can’t reach him now.”

“Oh, can’t I?” Acheron threw a feint at his chest, driving him back onto another moving platform. The Doctor scrambled back, but not before his opponent had swapped his sword to his off-hand, drawn the laser and fired.

Screams from the mezzanine showed that some witnesses had arrived to take in the spectacle. The blinding explosion drew the Doctor’s attention away momentarily. The beam had burned a great swath of nothingness across the dance floor. For a frantic moment he thought Nyssa had been caught by the blast, then he saw her crouched behind a heap of debris.

“The TARDIS!” he called, fending off a blow that grazed his scalp.

Nyssa moved just in time. As the missing section began to reform, another shot took out a different part of the floor.

“Are you mad?” he barked at Acheron. “Keep this up, and the whole building is going to unravel!”

There were other vulnerable bystanders besides Nyssa, although they were now being herded towards the exits by the guards. The Doctor redoubled his efforts, no longer trying to disarm but duel in earnest. He would maim if he must. Reverting to right-handed sparring, Acheron fought back savagely, still squeezing off random shots in Nyssa’s direction. More blinding flashes erupted. The floor vanished wherever the beam struck. Some of the panels did not return.

The guard who had been swept away had picked himself up, and was making for Nyssa. He never reached her. The Doctor was too busy trading blows with Acheron to see clearly what happened, but he heard the scream as the guard fell through a coloured pane that appeared solid. The man’s cry faded into the distance. With the transmat still in lockdown, there was no chance of being whisked to safety. This was serious. If the floor’s tinted surfaces were no longer a reliable indicator of solid ground, any step could be a trap.

“Nyssa, hold still!” he cried.

“Nyssa?” Acheron gaped at him. Then the man threw back his head and laughed. “Of course! Of course! How blind we’ve all been! This weakling is no Apollo, but a mere girl. And as for the so-called King—”

His words were drowned out as the floor carried them through the rumbling torrent of water, but the damage was done. There was a light of malignant awareness in his eyes. The Doctor opened his mouth to speak, but he had come under the full force of the waterfall and was beaten to his knees. Acheron waited for the wall of water to pass before rearing back for an executioner’s swing at his stooped neck. The Doctor rolled to dodge and nearly landed on another illusory panel. He felt one knee dip below its surface and recoiled.

“Doctor!” It was Nyssa’s own voice now. “The floor! It’s failing!”

Slowly but inexorably, the outer circuits of the dance floor were disappearing. There was no longer a way to reach the ballroom’s fixed perimeter. The Doctor could do nothing to help her, pinned on one knee, fighting desperately to ward off Acheron’s hammer-strikes. At last, when the man again committed his full strength to a downward stroke, the Doctor saw his chance. Leaning away from the blade instead of parrying, he reached across the man’s body to hack at the gun. His exposed thigh was raked by the sword’s tip, but his own sword sheared clean through the barrel. And Acheron had overbalanced. The Doctor slammed his head and shoulders into the man’s shins, transforming Acheron’s stumble into a headlong fall.  He went flying and fetched up in the trough between two gyres far below.

The Doctor had miscalculated. Nyssa was down there! Snarling, Acheron scrambled to his feet and began to hop drunkenly across the peaks and valleys of the constantly-moving maze. The Doctor tried to chart a course that would reach her first, but Acheron was more familiar with the room’s 4D topography. Nyssa began to move away, but slowly, testing each panel’s solidity before stepping down.

“Doctor!” Nyssa called. “Console!”

“What?!”

He staggered as the floor lurched, shuddered, and morphed into a wildly different configuration. Peaks and valleys smoothed out, transforming the room into a huge six-sided pyramid with a bewildering array of circular zones of rotation, shifting polygons and unidirectional strips that flowed like conveyor belts. The middle of the room was now an elevated triskelion of three gyres that rose and fell in a large cylindrical unit. Apart from that, there appeared to be little rhyme or reason to any part of the floor. Acheron, who had been making alarming progress, was suddenly carried up and away from her by a swiftly-moving ramp.

“The floor!” she called. “Where should I go?”

Suddenly he understood and almost laughed out loud. It was a rough schematic of the TARDIS controls! Had she programmed all this beforehand, or used the Hierophant’s key to send telepathic commands on the fly? Either way, the battlefield was suddenly very much in their favour. They knew this layout by heart, whereas someone raised with the rational, mathematical geometry of the Celestial Basilica would find the TARDIS console utterly baffling.

Near the edge of the floor, it was difficult for Nyssa to see the overall map. But from his vantage point above her, the Doctor could direct her, taking advantage of the one-way conveyor belts — representing coordinate sliders, the door lever, the radiation and atmospheric sensors — to leapfrog across whole sections quickly. If only he could bring her to the real TARDIS before Acheron made sense of the chaos. The TARDIS was perched a third of the way around the rim from Nyssa, about where the databank screen would be.

Once upon a time, she had teased him for making the console’s operations into a dance. Now, that dance was theirs.

“To your left— referential difference display!” he sang out. “Close the scanner, then use the emergency override to cross to auxiliary power. Battery B at maximum, A powered down, artron gauge, and over!”

She began to weave and spin across the floor. He started down to meet her, taking a meandering path so as not to give away her moves in advance. Acheron swerved to cut him off. The man was growing intolerable. The Doctor abandoned his attempt to reach Nyssa, instead trying to mislead her pursuer.

Nyssa raised her voice again. “Dead end!”

Could anyone mistake her for Achille any longer, now that she was using her real voice? But the guards had fled with the spectators when Acheron started blowing up chunks of the floor, and they were just beginning to return. The Doctor turned back to the more immediate problem. It took him a moment to spot what she had seen: a rivulet of water draining through a section of floor that appeared solid. There was no telling how far the hidden hole extended.

“Don’t worry. Go back— scanner control open this time— to the mean free path tracker, the coordinate sliders—ah, that’s it, up and over— to lateral balance cone 3, air recycling, door lever open, ride the external sensors, chameleon circuit, and you’re there.” She had to circle two-thirds of the room, and he could only hope she would not meet another road block. “Have you got all that?”

“You’re only postponing the inevitable, Doctor!” Acheron said, stalking towards him. Apparently he had decided to eliminate Nyssa’s guide and then polish her off at his leisure.

“Many inevitable things are worth postponing, I believe,” the Doctor said, working his way down towards auxiliary power to draw his opponent away from Nyssa’s revised route. “400-year overhauls, for example. Also death. Speaking of which, I’ve heard they execute kingslayers here. You might want to reconsider your position.”

She was almost there. But then the Doctor saw he had simply guided her the long way around to disaster. The depression where the TARDIS stood had deepened into a crater, and the floor for some distance around it was flickering like a dying electric torch.

“Stop!” he cried. “The TARDIS is destabilising the floor!”

It was only a question of whether the erratic Hostile Action Displacement System kicked in before that side of the room failed altogether. Sure enough, the wheeze of engines announced his ship quitting the field. It faded away, leaving Nyssa stranded at the edge of the unstable zone. The chameleon circuit had always been unlucky, and that was approximately where she was standing now.

The Doctor was so distracted by her predicament that he had forgotten about their foe. Nyssa shouted a warning. Half-turning, he saw Acheron barrelling down on him from above. There was no time to dodge. The man’s eyes blazed with murderous triumph as he threw his whole weight into a sword-thrust that would run the Time Lord through. But the blow never reached him. Acheron’s roar of victory changed to fear as his front foot sank through another weak spot. The Doctor grabbed for his shoulders as he went down. But the man shrugged him off and dropped into the abyss with a dreadful cry.

Looking around, the Doctor saw that Nyssa’s plight was becoming desperate. The section where she was standing had turned completely transparent, with no misty surfaces to show its boundaries. The guards were converging on her position, but they could not reach her. The three metre gap between her and the solid rim of the ballroom might as well be a chasm.

The Doctor calculated vectors, dropped the Hierophant’s sword and began to sprint, praying he would step on no trick panes. His torn leg was burning, but that did not matter. He stumbled, ran, stumbled again, threading the shifting tracks with singleminded precision. With a final burst of speed, he pushed off, launching himself into space.

Mind the gap.

Nyssa saw him coming and leapt in the same direction. He caught her roughly around the waist, her own momentum ensuring that his was barely slowed by their collision. They crashed down together on the far side. Reaching arms seized her cloak and doublet to keep them from falling back into the abyss. They rolled to a halt with the Doctor on top. He remembered that half her face was exposed, chin to right cheekbone visible where the mask had broken diagonally. There was little hope she could pass herself off as Achille now. Wisely, she kept quiet, pressing her face against the floor. He gave her a silent squeeze.