River is touring Starship UK in style, posing as the Queen of Scotland. She has the feeling she's not long missed the Doctor. There's something of him in the air: optimism, barely controlled chaos and burnt TARDIS handbrake.
There's a commotion going on slightly further along the promenade and River recognises the woman at the centre of it. Well, she would. Queen Elizabeth the Tenth's face is on all the currency, even the forged notes River is carrying.
It looks like Liz X recognises River too because she breaks away from the crowd surrounding her, throws her arms around River's neck and kisses her.
Now this. This is what River likes best about time travel. The Doctor can say what he likes about adventure, discovery and saving planets, give River being snogged by a relative stranger in front of what looks like half the British government any day of the week.
Liz X pulls back and grins at River. "I've just abdicated."
"I'm pleased for you," River hazards. She senses the Doctor somewhere behind this.
In the middle of the Doctor's leftover chaos and the confusion caused by their Queen kissing strange women in public, someone in the government catches their breath long enough to say: "Hang on, there isn't a Queen of Scotland."
And River gets thrown in jail. Again.
"Open the door, I'm the bloody Queen!"
River's only just met Liz X, but she thinks she likes her.
"I understood you'd abdicated. Er, ma'am. Sorry, ma'am."
There's a pointed silence and then the cell door slides open and in walks the (former) Queen Liz X.
"You know me?"
"The kiss didn't give it away?"
River shrugs. "You're only human."
"I've got something for you." Liz produces something that River instantly recognises as a vortex manipulator from inside her cloak and passes it through the bars.
"Where did you get this?" asks River.
"You're going to give it to me."
Liz X finds River Song sitting on her throne carefully adjusting a crown on top of her curls.
"Ah. Your Majesty."
"Bit of a problem. I might need to pose as the queen of Starship UK for a couple of days. You don't mind, do you?"
"Who am I meant to be, then?"
"People get beheaded for treason to the crown, you know."
"Royal concubine, then."
The Royal bed might have the only mattress in the universe more comfortable than River's own onboard the TARDIS, and she really thinks Liz ought to be celebrating her golden jubilee in bed with River, rather than pacing the room and worrying.
"There's something wrong with this ship," she says. "I know it."
River lifts her head from the mountain of pillows. "It's the engine noise. There isn't any. Took me ages to get used to it. Now. Come back to bed."
River is sitting on a sun-dappled terrace. She's looking out over a beach of pink sand and sipping a green cocktail. Beside her the Doctor is nursing a drink with seven decorative umbrellas in it; it's Pretty Boy and he's got his trainers up on the table.
"I've had Queen Elizabeth," he says, apropos of nothing.
"Which one?" she asks.
"I've had Liz X."
"I don't think I've met her yet."
"Something to look forward to."
River convinces the Doctor -- the one she's travelling with at the moment, the girl, who she thinks is the one after Babyface, unless there's another in between who she hasn't met yet -- to take her to see the Exodus from Earth.
And it's sad. It's like that sometimes, with the Doctor. Something that's archeologically fascinating from a couple of hundred years away is different up close.
River breaks into Buckingham Palace. She finds Liz X standing on a balcony, gripping the railings and staring out into nothing.
"Children screaming," Liz says, without turning round. "All I can hear is children screaming."
"It'll be all right, ma'am," River says. "In the end."
Liz turns round. "I've seen you before, you were at my coronation."
"Are you the Doctor?"
River sometimes lets people believe what they want to believe, and sometimes she lies outright. Not this time. "No. You'll recognise the Doctor: higher alien intelligence and the hair of an idiot."
Which is a pretty accurate description of all the Doctors River has met so far.
River does attend Liz's coronation. For a certain definition of attend, anyway.
She's making a quick getaway from a team of Time Agents after she's lifted a vortex manipulator from one of them while he was making her breakfast. She falls through a tear in the vortex and lands in a heap at the foot of the throne.
"Liz, what a lovely surprise. Are you busy just now?"
"Apart from the coronation, you mean?"
River looks around the grand hall, it's crammed with people and recording equipment. Her ignoble entrance has been televised. Excellent, she must get a copy of the tape for the Doctor. Then she feels the shiver of static electricity that preludes oncoming Time Agents.
River hops easily to her feet, hooks her arm around Liz's neck and drags her in for a quick kiss; with her free hand she stuffs the borrowed vortex manipulator down the queen's cleavage.
River pulls back. "Love the crown," she says, and with that and a final wave at the cameras she turns and runs down the aisle.