The Doctor and Lorna sat on a bench made just for adults, frowning at the playground straight ahead. As they looked at its various shapes a glass tube popped out of the ground, which stored strings of coloured lights and a slowly rotating sheep.

“It’s all very odd,” said the Doctor.

“I don’t think the people who built this place knew much about eleven-year-olds,” said Lorna.

The Doctor looked at her with a disbelieving grin, then started laughing despite herself.

“That wasn’t funny!” said Lorna. “You don’t laugh at my actual jokes, and then you go laughing at that!”

“Sorry! It’s just… it’s a very human thing to say. Sometimes I forget, how it’s different being human. With your one heart and your horribly rapid aging.”

“And would it be very human if I slapped you in the face?” said Lorna without any malice. “Laughing at me like I’m stuck in your Time Lord zoo.”

“I don’t know how you do it, that’s all,” said the Doctor. “Your species. How you can see something like the Daleks one minute and the next you’re all fussed about a playground. How that first thing doesn’t overwhelm the other. ‘Cause I’d go insane, if it were me.”

“That assumes,” said Lorna, “that I didn’t go insane.”

“Oh.”

“What’s sanity, anyway? In a place like this. With the evil felt, and this really terrible playground. Or even without them. Sometimes I don’t know what it’d even look like, to be sane.” She sighed. “I just can’t get a handle on things.”

The Doctor looked past the playground to a steep road, which looked completely ordinary as people walked up it and down. At nightfall Daleks would come down it fast as cars, and in the morning there’d be no people left on it at all.

“I still can’t get over how small it was,” said the Doctor.

“I don’t know what you’re talking about,” said Lorna. “You’re a bit like a crossword, sometimes.

“What? Oh, the Daleks; the way they’d change. I thought it’d be bigger than this.”

“Why’d you think they would change at all?” asked Lorna, who knew the answer as soon as she’d said the words.

“That siren wasn't for her birthday,” she said.

The Doctor shook her head.

“The TARDIS would've timed it like that. Understood the warning, waited. Knows a lot, she does, about how to put on a disguise.”

The Doctor sighed, and looked down at the pebbled ground.

“I trust you enough to tell you the whole truth. But I can’t tell Chris, and you can’t do that either. It’s too big a thing for a child. Especially one who’s gone through a very big number of things.”

“You’re not her mother, Doctor. I can make up my own mind on that.”

The Doctor smiled sadly. “But I’m still her psychiatrist, right? And in my position, any doctor’d feel that they’d have at least some responsibility.”

She pulled up closer to Lorna on the bench. “This is a long explanation. A lot of talking. You don’t have to listen to all of it.”

“You already know,” said Lorna, “you won’t keep me from the truth by babbling on.”

“Then here goes,” said the Doctor, squinting up at the city’s false sun.

“That future we saw,” she began, “where the Cybermen won. It’s still out there, in some way or other, but it’s not now a part of space and time. Can’t access it, no going back. Kicked straight right out of the universe. Because what the universe is, it changes, right? Like a sort of… big quilt, that’s constantly shifting its shape.”

“That’s a very bad analogy,” said Lorna, “but I understand what you mean. And you think it’s all changing to be more Daleky?”

The Doctor shook her head. “Worse than that. Worse than anything. When a Time Lord hears that sound flash through her TARDIS, well… we call it the death of hope.”

She looked up at the safest sky in the universe, as the sun bled through the air and the lack of clouds.

“It's called the Fell Siren,” she said, “and it's only sounded once before. And it means that possibility is close to collapsing, that the universe is changing into something that can’t change shape any more. The Shape of the Dalek; Daleks everywhere and everywhen, with no chance that any of it could be changed. They call it the Dalek Eternal; it’s what Jessica was built to bring about. And it’s what they were fighting for, long ago. Wresting time and space from my people so that everything would be like them. And they almost did it,” she said. “We were all becoming Daleks, towards the end.”

Lorna took a deep breath. “But they didn’t win?”

“No. There was a miracle, and it turned out I’d planned it all along.”

“And you’ve got some more of those miracles, which’ll all be coming along soon?”

“Not quite. I have two ideas. They’re both awful, and neither of them’ll work. But I have to try.”

She looked over to Chris coming back from the playground underside, emerging from something like an upside-down Christmas tree.

“When I first met your daughter, Lorna. I told her to see the beauty in everything. Because it is beautiful! Even this playground is, if you really screw up both your eyes. And the beauty that’s here doesn’t go away now, even if it might go away forever. ‘Cause where there’s life there’s hope, and where there’s hope there’s life, and if both of those things are in danger, well.”

She smiled at her friend.

“Then you don’t need me to tell you to keep her safe. But I do know that’s harder, than anything I might have to do. I know its a weight, and a different responsibility. But we can’t forget it, any of us, now the Daleks are warping the world.”

The Doctor walked off in a direction that didn’t make sense. She was old, Lorna knew, but that level of fear had seemed new to her– like after an impossible volume of time she’d finally understood she could die. As she looked at where her friend had been she felt somehow far older and younger than her, and something felt strange about the whole concept of time.

Christina walked half-slouched towards the bench, her hands in her pockets and her eyes looking old and dull.

“I’m sorry about the playpark, love,” said Lorna to her daughter. “Children probably like different things, now we’re here in the distant future.”

“There was a Dalek, and it was going to kill me,” said Chris. “But I killed it, with my special can.”

It all hit Lorna then, the stupid amount of danger the Doctor had put her child in by giving her a dangerous weapon, and the even stupider fact that they’d come somewhere where you’d need to use it to survive. And the fact that was worse than that, if the Daleks would soon come through everywhere– that being friends with that incredibly dangerous woman might mean her daughter was the safest person in the universe.

She smiled at Christina, hoping she showed no fear.

“We’ll have to get you out of here, won’t we?” she said, wrapping her child into her arms. “Before it gets even less safe. But you’re safe here, now, away from that stupid old Dalek. You’re safe in my arms here with me.”

They hugged each other tightly under the spattering rain.

All over the city, people kept casting votes for the Daleks.