Marianne hadn't really been aware of how often Chrestomanci went to other worlds until he started taking Cat with him.

“It's not that often, really,” Millie told her, lining up sugar mice on the desk in front of them. “They're busy at the moment trying to set up a cross-series agreement for returning prisoners, and the diplomacy is keeping them frazzled. Now, try to put a little more force into it, this time.”

Millie was teaching them battle magic, which Marianne was very bad at. Sighing, she tried to call down lightning on the nearest mouse, but she was distracted thinking about other worlds, and all that happened was that the mouse turned blue and a few sparks came off its nose.

“Don't be such a wimp, Marianne,” Julia said, giggling. Julia was very good at battle spells. “You have to really want to smite them.”

Marianne didn't really have anything against the sugar mice. She didn't really want to learn how to smite someone, even if Julia thought it was the most fun since bicycling. She was much more interested in other worlds.

Julia's sugar mouse sizzled and then went up in a ceiling-high column of flame. Millie doused in hurriedly and then clicked her fingers to clean the soot off the ceiling, not for the first time. “More control needed, darling.”

“Sorry, Mummy,” Julia said, and it was Marianne's turn again. This time Julia winked at her as she began to raise power, and Marianne looked down to see the sugar mouse had now been spelled to wear her Uncle Lester's face, pink and squeaking. She choked on laughter as she released the power, and the mouse melted with a sudden stench of ozone and burnt sugar.

“Mmm,” Julia said and grabbed part of the crunchy shell which was all that remained. “I love that smell. I never leave enough over to actually eat.”

“That's why you need for self-control,” Millie told her, laughing, and turned away to get the next tray of mice.

“Whose face are you putting on yours?” Marianne whispered to Julia.

Julia's face went thunderous, dark brows drawing together in a scowl. “That stable boy,” she pronounced.

Marianne hastily changed the subject, having heard far too much along that line recently. She had tried to warn Julia and Janet that all Hopkirks were all looks and no character, but they hadn't listened. “Does going to other worlds hurt?”

“I don't think so, no,” Julia said. “Why?”

“Cat,” Marianne said. He'd been limp and miserable for weeks, and not in the normal Cattish way that meant he was being ridiculously stubborn about something and trying to hide it.

“Janet's worried too,” Julia said, sighing. “It's not the travel that's the problem. It's that girl. I don't think it's fair of Daddy to make Cat go.”

“I don't think he's enjoying it much, either,” Millie said. “She does reserve a certain hatred for him. Unfortunately, we do need all the worlds in the Series to cooperate on this, and I'm afraid that means they have to work with her government. I gather she's making it difficult for all the negotiators. It's a miracle no one's tried to bump her off yet. Is Cat very unhappy, Marianne?”

And the explanation that followed was the first time anyone told Marianne about Gwendolen.

That evening, Cat went straight to bed as soon as he came home. Janet, who went to check on him, reported that he hadn't even spoken to her, just stuck his head under the pillow and wished for her to go away. “Or, at least, I assume that's what it was, because I found myself six feet down the corridor and stuck to the wall. I had to leave bits of petticoat there.”

“I'll clear it up later,” Marianne said. “What are we going to do?”

“Klartch,” Janet demanded. “How do you feel about eating people?”

“Maybe,” Klartch said, with a speculative gleam in his eye.

“She'd stick in your throat,” Roger said. “Too much hair and lots of frilly bits.”

“I remind you,” Janet said coolly, “that she's my exact double.”

“Yes, but you don't look anything like her,” Roger said and Julia nodded vigorously.

Marianne, who suspected they were about to drift off the point, repeated, “What are we going to do?”

“I don't know,” Janet said glumly. She had found a notebook and pencil and was poised to note down their plans. “And I don't think your father has any idea, either. I happened to overhear him talking to Millie on my way back and he said all manner of things I don't think he would have if he knew I was listening. My vocabulary is considerably expanded.”

“Can't we stop Cat going on these trips?” Roger suggested, at the same moment Julia murmured, “I could smite her.”

“Diplomacy,” Marianne stressed. “He has to go, and she has to be kept cooperative enough to sign the silly treaty. But, maybe, he doesn't have to go alone.”

“You mean one of us could go with him and distract her?” Roger said. “Yes, or threaten smiting, thank you, Julia. I dunno if Dad would-”

“He'd let Marianne go,” Janet said.

“Me?” Marianne squeaked in alarm.

“You are an enchanter,” Janet said, tapping her pencil against her lip thoughtfully. “I'm sure it's something you'd have to do eventually. You should ask him.”

“But-” Marianne wailed.

“I think that's an excellent idea,” Julia announced. “He likes you.”

“He does not,” Marianne protested in dismay, and then rethought that. “He likes all of you! You're his children.”

“Quite,” Julia said.

“He's used to us asking him for things,” Roger explained placidly. “He's more likely to say yes to you.”

Janet took pity on her and said, “We could ask Millie to ask for you.”

But Marianne was sick of people implying she was a coward. “No. I'll do it.”

It was worth the nerves just for the sudden smile on Cat's face when she stammered out the request.

“Offworld?” Chrestomanci echoed vaguely. “If you like. It's terribly dull, isn't it, Cat?”

“Awfully. Full of people talking,” Cat agreed, but he was still smiling. She hadn't realised just how long he had been miserable until now.

“Oh, but it won't be boring for me,” Marianne said hurriedly, so Cat didn't suspect there was a plot. “I've never even been to London.”

“Never?” Chrestomanci said, eyebrows arching. He sounded vaguely appalled.

“Well,” Marianne said, feeling she ought to be scrupulously honest. “We had a school trip to the Great Exhibition once, if that counts, but the charabanc took us right to the door. Mum says that Hopton's fancy enough for us, if we can't get what we want in the village.”

“Good Lord,” Chrestomanci murmured, still staring at her as if she was a creature from another planet. “Er, we were discussing the summoning of spirits.”

Evidently, though she had troubled him, because he kept her back for a moment after he had dismissed Cat. “This, er, trip offworld-”

“I just wanted to do something different,” Marianne said quickly. They had all agreed that protecting Cat was probably one of those things where it was better to get permission afterwards. “I mean, I've not doing very well with the battle magic, and I thought a change might help.”

To her horror, he went all nice and understanding, which had always used to make her wish the floor would open up and swallow her, until they day when it actually did and Cat had laughed so hard he hit his head falling off his chair.

“I wouldn't worry about the smiting,” he said kindly, and smiled as if he was inviting her to share the joke. “We can't all be as bloodthirsty as Julia.”

“No, er, I mean thank you,” Marianne stammered and fled.

It wasn't until she saw Gwendolen that she understood what Roger had meant about Janet being different. Janet was undeniably lovely, but she wore her beauty in an unconcerned, careless way, and would have been mortified if anyone implied that she was the prettiest child in the Castle. Gwendolen, on the other hand, looked like a chocolate box painting, all prim and simpering and liable to stain the tablecloth if someone knocked a glass of water onto her.

She was also the most objectionable person around the negotiating table. They were meeting in her court because she refused to take part otherwise, yet she was late to every meeting, and clearly had little interest in the proceedings. Marianne wondered why she hadn't just palmed off the task onto a functionary, as she seemed to do with any other problems that were brought to her.

Then she realised that Gwendolen was demanding a recess every time either Cat or Chrestomanci put forward an idea. As the rest of the council were looking to Chrestomanci for guidance, nobody appreciated this, but the merest hint of censure brought on quivering and the threat of tears.

Marianne was not impressed and she let it show.

Gwendolen clearly did not know what to make of her. Cat she loathed, so clearly and absolutely that Marianne felt sick just from being close to it, and now she knew why Cat had been coming home so pale and drained. Gwendolen was not much of a witch, but she didn't need to be with that much hatred. Chrestomanci seemed to scare her, though a little of that same loathing was sent his way.

Marianne very casually moved her chair so Gwendolen would have to glare right through her to get to Cat. Beside her, Cat let out a little breath of relief, and Marianne turned her own glare on Gwendolen, the nastiest, most Gammer-ish look she had, the one that made her look square and mean and sour. She thought it was the sort of look Gwendolen would understand.

It worked, for a while.

But then they were served with dinner, and Marianne was overwhelmed with dismay. She had no idea what most of the foods were, let alone how to eat them. Beyond that, the fashion here seemed to be to eat lounging sideways on a couch, whilst balancing your plate precariously on the edge of your seat, and Marianne was very bad at it. Cat was no help at all, mostly because the footmen had obviously been instructed to serve him from the right and he kept jumping and spilling things.

“Your sister may be the pettiest person I have ever met,” she remarked to him.

“She doesn't improve upon acquaintance,” Chrestomanci remarked, and she hadn't realised that he was almost as badly off as Cat until she looked at him. He was faintly green around the mouth, and he seemed to have given up on eating the little purple things with stringy tentacles. “Cat, correct me if I'm wrong, but am I the only person here who doesn't have golden cutlery?”

“Oh, for goodness' sake,” Marianne said, starting to understand why Janet and Julia were the way they were. “Swap, then.” She hurriedly wiped her own knife and fork on her napkin and dropped them on his plate, taking his silver ones right out of his hands.

Chrestomanci was still regarding his plate with suspicion. “I suspect she'll poison the fish next.”

“She tried that three days ago,” Cat said glumly. “I turned it into extra salt. I'm used to people being good at food.”

Marianne closed her eyes, hoped for strength, and dealt with the footmen next. It was as easy as stopping one and saying, in the most no-nonsense way she could, “Serve him from the left, please. He's got a cunning hand.”

The footman looked embarrassed. “My lady, the queen insists-”

Marianne cut him off with a shake of her hand, feeling very grand and pompous. She had been the Grand Vizier in the school pantomime the Christmas before she left, and she tried to put that attitude back on. “As the queen desires, of course. It is not my place to speak. However,” she added, leaning forward, “the queen is known to test the loyalty of her servants, is she not?”

The little shake of his shoulders was enough to tell her she had guessed right. Raising her eyebrows, she looked at Cat, then across at Gwendolen, and nodded in the most meaningful way she could.

She saw the moment he spotted the resemblance and settled back in her seat as he retreated, bowing. Whatever orders Gwendolen issued now, every servant in the place would be convinced Cat was royalty by morning.

“What happens next?” she asked, turning back to the others.

“More talks,” Tom, Chrestomanci's secretary, said, dropping her a wink behind the others' heads. “And we'll try to move towards signing the treaty and then, out of nowhere, we'll be adjourning for the night.”

“Do you ever get anything done?” Marianne asked.

“Behind the scenes, mostly,” Tom said. “The big public meetings are for show. You're welcome to come with me to some of the other talks this afternoon and see how it really works.”

To her surprise, Marianne really wanted to do that. She looked to Chrestomanci for permission, but he was staring across the hall.

Gwendolen was storming towards them, the pages who carried her train scurrying to keep up. Obviously, she was not impressed by Marianne's interventions. Marianne hurriedly shoved her plate under the couch and stood up to meet her.

“Get down,” Cat said suddenly and urgently, grabbing her skirt and hauling.

Marianne toppled back onto her couch, and then rolled hurriedly as Cat kept pulling. She was in time to see a bodyguard suddenly slam Gwendolen to the ground, and sickly scarlet light lashing down across the hall, slicing through banners and tables and floor alike, and someone up in a balcony lean forward, a horribly bulky gun swinging round to target Gwendolen again.

Millie had been right. Somebody really was ready to murder the stupid girl.

The problem was, Marianne saw with the clarity of terror, was that any bolt which passed through Gwendolen would hit them too, and it would probably tear them apart as easily as it had the floor.

Luckily, that was the moment when she discovered that she could smite somebody quite easily if she was scared enough. The lightning arched down out of nowhere, the would-be assassin lit up with an unearthly screech, and then toppled off the balcony, and hit the ground still steaming.

As chaos erupted around them, Marianne stood exactly where she was, shaking more and more with every breath. It wasn't until Cat grasped her wrist and said, “He's up, though the guards have him. I think you just stunned him,” that she felt able to take a proper breath.

“I'll send these two home,” Chrestomanci said quickly to Tom. “Can you start finding out whose partisan-”

But Gwendolen had arrived. Her golden skirts were torn, her elaborate hairstyle had collapsed on one side and her make-up was smeared down her cheek. She was battered and furious.

“You!” she snarled, jabbing her finger at Cat. “Somehow, I know this is your fault.”

“The sooner we remove ourselves the better, I believe,” Chrestomanci remarked over her head, which even Marianne knew was the worst possible way to deal with her.

“And you!” she screamed. “You're determined to ruin my life! I don't care about your stupid treaty! I'm never going back.”

Chrestomanci looked puzzled. “Whatever makes you think we want you back?”

Cat sighed a little, and Gwendolen stamped her foot a little and turned on him. “I suppose you think I'm going to be grateful now? Saving my life is no more than you owe me, and-”

“Oh, please,” Marianne said, having finally had enough. “As if we waste his talents on such minor things. Go and sit yourself down before someone else decides to shoot you.”

Gwendolen gaped at her, mouth flapping. Marianne stared back, trying to convey I can smite you too as hard as possible. It must have worked, because Gwendolen took a little step backwards, and then another and another, her feet carrying her away faster and faster as Marianne pushed.

By the time she was back in her seat, the mess had been cleared away, and the servants were bringing in dessert. Nobody was quite looking at Gwendolen.

They went home with a treaty, and next time Marianne was faced with a sugar mouse, she vaporised it quite easily.

“I still think it's a shame you didn't let the assassin get to her,” Julia said and stuck gold curls on her next mouse. “Don't look at me like that. I'm joking. Mostly.”

“I know,” Marianne said and wondered when she could go offworld again. She thought diplomacy might be rather fun.