Anomaly

1 Billion Years Later, At somewhere in space.

The console room hummed with the low, contented sigh of a TARDIS at rest — not idling, exactly, more like a great sleeping animal breathing between adventures. Clara Oswald sat cross-legged on the jump seat, wringing seawater out of the hem of her cardigan, while the Doctor circled the console barefoot, leaving wet footprints that the ship seemed to be quietly, disapprovingly evaporating as fast as he made them.

"I'm just saying," Clara said, "a planet that's entirely ocean. No coastline. No beach. No little umbrella in your drink because there's nowhere to put a bar."

"There was a floating bar."

"There was a raft with a fish on it who mixed cocktails with his tail."

"Best mixologist in three galaxies, that fish." The Doctor flicked a switch, frowned at the readout it gave him, and flicked it back. "You're just annoyed you lost the swimming race."

"I was winning the swimming race, until something the size of a bus decided I looked like lunch."

"You looked delicious. I told you, that colour suits you." He grinned at her sideways, the kind of grin that always meant he was proud of himself for something only he found funny yet. "Besides, technically you didn't lose. You achieved a highly efficient tactical retreat."

"I screamed and climbed you like a tree."

"Like I said. Tactical." He straightened up, wiped his hands on his tweed — which did absolutely nothing, since his hands were still faintly turquoise from the planet's bioluminescent shallows — and beamed around the console room as if it were the finest view in the universe, which, depending on the day, it occasionally was. "Best fully-oceanic planet in the whole of the Local Group, that one. No name yet, as it happens. Native life hasn't invented one. Bit rude of us to have visited a whole world and not even know what to call it, really."

"So name it."

"Can't. Rules." He said this the way he said most rules — as though they were both sacred and enormously fun to have just broken. "Naming rights go to the first species to develop written language. They're only up to interpretive bubble-patterns at the moment. Give it another eleven million years."

Clara opened her mouth to say something about patience not being either of their strong suits, when a sound cut across the console room — small, tinny, entirely wrong for a time machine the size of a cathedral inside a police box. A ring. An old-fashioned, insistent, brring-brring sort of ring, coming from the ancient black telephone bolted to the console, the one Clara had always assumed was decorative, in the way that everything on the TARDIS was decorative right up until the moment it very much wasn't.

The Doctor went still.

"Is that—"

"It's the phone." He said it quietly, almost reverently, already moving.

"I didn't know it actually worked."

"Everything works. Eventually. That's rather the point of it." He picked up the receiver, and for a moment his whole face changed — the easy grin folding away into something older, more careful, the face of a man doing sums no one else could see. He didn't say hello. He never said hello to this particular caller; Clara would learn that soon enough.

"Yes," the Doctor said instead, listening, nodding once at nothing, his knuckles pale around the receiver. A pause. Longer this time. His eyes flicked, just once, to Clara, and away again. "Yes. I understand. Hold tight — don't do anything until we get there."

He set the phone down with a click that seemed far too loud for such a small, ordinary sound.

"Doctor?" Clara was on her feet now, cardigan forgotten. "Who was that?"

He was already at the console, already throwing levers, already wearing the particular expression he wore right before the floor started shaking and the world outside the doors stopped being safe. The great central column began to rise and fall, and the ancient engines groaned their familiar, impossible groan.

"Old friend," he said. "Rather insistent one. Tends to be, when there's a war on."

"A war? Whose war?"

The Doctor didn't answer straightaway. He was too busy grinning again — but it was a different grin now, sharper at the edges, the one that meant he'd already decided this was going to be enormous, and possibly on fire.

"Hold onto something, Clara," he said instead. "We're going to see Winston Churchill!"

"The Winston Churchill?" Clara said, disbelief written all over her face.

The Doctor just smiled and flipped the dematerialisation switch. The ground started shaking, and the TARDIS started up that humming noise — that deep, groaning, wheezing sound that meant the universe was about to be rearranged around them, whether it liked it or not.

Questions started flowing through Clara's head, and she began asking them rapidly. How does Winston Churchill have your number? Does he know about the TARDIS? How did you two even meet?

"I met him a long time ago," the Doctor said. "He's a friend" — not answering any of Clara's questions.

The central column slowed its pumping, the wheezing groan deepening into something lower, heavier, almost tired — and then came the sound Clara had already learned to brace for: a series of scraping, shuddering thuds, like the TARDIS was dragging its heels on the way down. The lights along the console dimmed once, flickered, and steadied.

They'd landed.

The Doctor was already straightening his bow tie in the nearest reflective surface, looking entirely too pleased with himself for a man who'd just refused to answer three perfectly reasonable questions.

"Well," he said, striding for the doors. "Best behaviour, Clara. Difficult year for old Winston, this one."

"Which year?"

He paused, hand on the door, and glanced back at her with that maddening half-smile.

"Come and find out."

He threw the doors open.

Clara started walking rapidly toward them, excitement written all over her face — the kind of excitement that came with every single landing, no matter how many times she told herself she was used to it by now. She stopped dead in the doorway.

They were standing on top of a building, wind cutting sharp and cold across the rooftop, and below them sprawled a city she almost didn't recognise. 1939, the Doctor had as good as said. Britain. And spread out beneath her in the grey light was mile after mile of wreckage — collapsed roofs, blackened brick, streets half-swallowed by rubble, the whole skyline scarred in a way no history book photograph had ever quite prepared her for.

"Doctor," she said quietly, all the earlier questions gone out of her voice. "What happened here?"

"War," the Doctor said, his face suddenly sad.

He turned and started down a narrow flight of stairs without another word. Clara followed him, as she always did.

When they reached the bottom, the place was chaos — hundreds of people talking over one another, papers changing hands, a current of panic running under everything like a live wire. This was the command centre of the war.

The Doctor and Clara started making their way across the chaos, weaving between desks and running aides, and it was clear he was searching for someone. Clara guessed it was probably Churchill. They searched for three or four minutes — hardly any time at all, really — but to Clara it felt like a great deal longer, the noise and the panic stretching every second thin.

Finally they found him. He had a big, twirly moustache, a black and long hat, and a fat Cuban cigar clamped in the corner of his mouth. The moment he saw the Doctor, his whole face lit up. He plucked the cigar from his lips and said:

"Doctor. It's not going well here. They've surrounded us from all sides."

"You know I can't, Winston," the Doctor said, his face full of apology.

"I know, I know — we're just trying to hold on to something here. But that's not why I called you." He started walking through the chaos of the room with an ease that seemed entirely out of place, and continued, "I called you because there's something not normal here. Something... something you, I suppose."

The Doctor and Clara exchanged a curious glance as they followed him.

Churchill made his way to a wall in the middle of the room, reached into his jacket pocket, and pulled out a key. Clara wondered why he was standing in front of a plain stretch of wall — was there a secret door?

There was. Churchill leaned his weight against it, and the wall began to move. Clara glanced around; everyone in the room was far too busy to notice three people slipping through a wall that apparently wasn't a wall at all. Or maybe, she thought, they already knew it was there.

They stepped through, and there was another door waiting on the other side. Churchill worked the lock with his key and pushed it open, already moving through it as he said, "Come on, hurry up!"

Beyond it was a thin, unlit corridor, with a set of stairs descending into darkness at the far end. At the bottom of the stairs was a small, unlit square room. They stepped inside — and there it was. The reason Churchill had called the Doctor.

Stretched across the middle of the room, from one wall to the other, was something that didn't quite belong to any category Clara had words for. A kind of invisible wall, opaque and shimmering, like a sheet of liquid standing upright — and it was moving, slowly, rippling in on itself the way water does when nothing is meant to be disturbing it.

The Doctor looked at it with that curious face of his, the one he always wore right before something got interesting, and started making strange rubbing motions in the air near it — never quite touching it. Amazement crept across his face, and he whispered, "A space-time crack."

Churchill looked on like a proud father watching his child take its first steps.

"So what does it do? Why is it here?" Clara said, excitement filling her voice.

"It's a crack in the fabric of space and time," the Doctor said, still inspecting it closely. "It can open onto anywhere in space, at any point in time."

"So it goes somewhere? Like a portal?"

"Exactly. Anywhere. Anytime."

And with that, he jumped straight into the anomaly and vanished.

Clara didn't hesitate — with the same excitement still lighting up her face, she jumped in right behind him.

Churchill sighed, tucked his cigar back between his lips, and returned to his work as though nothing at all had happened. As though it were just another Tuesday.

When Clara climbed out of the crack, she found the Doctor already standing a few paces off, looking out at the horizon.

The planet was covered in sand. Not dunes here and there, not a stretch of desert between two greener things — sand all the way out, in every direction, until the ground and the sky agreed to stop arguing about where one ended.

"This planet feels similar," the Doctor said. "Maybe even familiar." He was clearly running through strange scenarios in his head.

Clara turned to him, her face troubled. "How come?"

The Doctor stuck his finger in his mouth, then held it up in front of him the way he'd hold the sonic screwdriver. Except it was just his finger. He seemed to be calculating something.

"I feel like I've been here," he said. "But I can't quite put my finger on it."

He smiled at his own joke.

"Oh — also, the city's that way." He said it with complete confidence, pointing off into the emptiness with the same finger he'd just licked.

Clara stared at him, mouth slightly open, trying to work out how on earth he could possibly know where a city was.

While Clara was still trying to work out how the Doctor knew where the city was, she started to hear a sound — a buzzing, somewhere out in all that sand. An engine, she thought, or something close to one.

A man appeared out of nowhere. A bandana across his forehead, enormous sand goggles over his eyes, a mask covering the lower half of his face — and beneath him, a motorcycle. Not an ordinary one, either. It hovered a hand's width above the sand without ever quite touching it.

He pulled up close and cut the engine.

"Hey. You two new here?" he said, tugging the mask down off his face.

"Yeah," the Doctor said. "Could you take us to the city?"

The stranger shrugged. "Sure. Get on." There wasn't a trace of worry anywhere on his face.

The Doctor and Clara climbed onto the back of the motorcycle, and he set off.

For the first minute or so, nobody said anything. The bike made a low, steady hum, and the sand went by underneath them in a pale blur, and Clara held on with both hands and tried not to think about how fast the horizon was arriving.

"So," the Doctor said, leaning forward, having to raise his voice over the engine. "Do you stop for everyone out here, or are we special?"

"Nobody's out here," the stranger called back. "That's how I knew you were new. People who know this place don't stand about in the open like that."

"Why not?"

"Because of the heat."

There was a pause, exactly one beat too long.

"Right," the Doctor said. "The heat."

Clara caught it too. She glanced sideways at him, and he gave her the smallest shake of his head — not now — and went straight back to being cheerful.

"Lovely bike, this. Antigrav suspension?"

"Something like that."

"Only, the field's about two hundred years ahead of the paint job." The Doctor patted the chassis with something like affection. "Which is a very interesting thing for a bike to be."

The stranger didn't answer that.

"What's your name?" Clara asked.

"Doesn't matter."

"It usually does."

"Not here." He said it flatly, without any rudeness in it, the way you'd tell someone the shops shut at six.

Clara looked out across the sand instead. There was nothing. No road, no marker, no track behind them — the bike didn't leave one, which she supposed was the point of hovering. Just the same emptiness in every direction, going on and on.

"Can I ask you something?" she said. "How do you know which way you're going? There's nothing out here."

"Same way he does," the stranger said, and jerked his chin back at the Doctor without turning round.

Clara turned to look at the Doctor. The Doctor was smiling, but it wasn't reaching his eyes at all.

They drove for five, maybe ten minutes. Then the shape of it came up out of the haze ahead — low buildings, sand-coloured, half-buried, and above them a scatter of towers that caught the light in a way that sand does not.

The bike slowed and settled, and the hum died away.

"This is you," the stranger said.

They climbed off. Clara's legs felt strange under her, the way they do after any journey where you've been holding on the whole time.

"Thank you," she said. "Really."

"Don't wander at night." He was already pulling his mask back up. "And don't tell anyone how you got here."

"Why not?" said the Doctor.

The stranger looked at him for a long moment through those enormous goggles. It was impossible to read anything at all in his face.

"Because you don't have the accent," he said. "And people notice."

Then he twisted the throttle, and the bike lifted, and he was gone back out into the sand — no trail, no dust, nothing to say he'd ever been there at all.

Clara watched the empty horizon where he'd been.

"Doctor," she said. "That man knew exactly who we were."

"Oh, he knew a great deal more than that." The Doctor was still staring after him, hands in his pockets. "He knew we'd ask for the city. He didn't ask which one."

He turned towards the buildings, and the grin came back — the sharp one.

"Come on, Clara. Let's go and find out what everyone here is being so calm about."

They came into the city along what seemed to be the main street. Buildings ran away to the left and right of them — some of them clearly expensive, with clean new-looking walls, and some of them old. Old old. Painted in strange, unique colours that had faded into one another over a very long time.

As they walked, people watched them. Not one or two. Everyone. Every person on that street, and every animal too, turning to follow them with their eyes.

Clara looked at the Doctor. He didn't seem remotely disturbed by it. She had the distinct impression he was rather enjoying it.

Then a child started walking towards them, and the Doctor slowed.

The kid came right up, stopped, and said, "Follow me." Then he turned and walked back the way he'd come.

They followed. It was the most curious either of them had been in a week, and that was saying something.

The child led them to a short brick building — plainly an important one, judging by the official-looking titles carved into the wall beside the door. They went inside. Clara glanced around as they crossed the hall, still wondering why a child had walked up to two total strangers in the street and told them where to go.

They went up a spiral staircase made of wood.

There was a man waiting at the top, in a room whose door had MAYOR written on it. They walked in. He was standing at the window with his back to them, looking down onto the main street.

He turned around.

"Hello, strangers," he said. "I'm the Mayor of this city. How can I help?"

The Doctor had a bad feeling.

Something was bothering him — or rather, someone. It didn't show on his face. Even Clara couldn't see it. But something was wrong.

After a two-second pause, he started talking.

"Hey, Mayo! What's wrong with your planet?" he asked, with a curious look.

The Mayor hadn't been expecting either half of that, and took both as somewhat rude.

"What do you mean, what's wrong with my planet?" There was a harshness in his voice now.

The Doctor paused, turned to his right, and started walking. He had entered his special teaching mode.

"There was a crack in the fabric of space and time. We went into it on Earth, in 1941, and we came out here. At..." He stopped pacing for half a second. "Where even is this place?"

"I named this planet when I found it. I'm the founder of this planet." The Mayor smiled. "It's called Skaro. Nice name, isn't it?"

The Doctor stopped.

He turned to the Mayor with a stunned look on his face.

"What did you say?"

"Skaro. The planet is called Skaro." The Mayor was trying to work out why the Doctor had given him that response.

"Skaro. The Skaro?" The Doctor's voice had gone strange. "But — isn't there a war going on?"

"A war? What war? There's no war here. We live in peace."

"Oh..."

He tried to get his energy back.

"Sorry. Then we haven't met properly, have we? I'm the Doctor." The charming grin returned as though it had never left.

"Good to meet you." They shook hands. "And this is my son." The Mayor pointed at the child they'd followed here. The kid smiled.

"Can I offer you something?"

"Tea?" the Doctor asked.

"Tea."

They started walking towards the far end of the long, rectangular room. Clara and the Mayor's son stayed near the door, watching them go.

And as the Doctor and the Mayor walked, the invisible wall reappeared.

The same one from Earth. The same slow, shimmering, liquid nothing.

It took them both. They were pulled in and gone in less than a second.

Clara and the boy stood frozen in shock.

Then they ran — both of them, without a word between them — and threw themselves in after them.

When the two of them came out of the crack, Clara and the boy looked at each other.

Because there was no sign of the Doctor. And no sign of his father.

They were somewhere else entirely. Somewhere with trees.

A forest. A real one — proper trees with proper leaves on them, and green light coming down through the canopy, and the smell of damp earth. After a whole planet of sand it was almost offensive.

Clara turned in a slow circle. No path. No buildings. No crack, either — the thing had closed behind them without leaving so much as a shimmer.

"Right," she said, mostly to herself. "Of course it has."

The boy hadn't moved at all.

He wasn't looking for his father. He wasn't looking for the crack. He was looking up, with his head tipped all the way back and his mouth slightly open, at a hundred feet of green.

"Hey," Clara said. "Are you—"

"What are they?"

She stopped. "...Trees?"

"Trees." He said the word carefully, the way you handle something you've only ever read about. He put a hand flat against the nearest trunk, then pulled it back, then put it there again. "It's wet. Why is it wet?"

"That's — that's just how they are. There's water in them."

"There's water in them." He looked at his palm. He looked at the tree. He looked at the several thousand other trees. "There's water in all of them."

Clara understood, then, and felt slightly sick about how long it had taken her.

Sand. All the way to the horizon, in every direction, with nothing in it.

"You've never seen a forest," she said.

"I've never seen a plant." He crouched down and touched the moss at the base of the trunk with one finger, very lightly, like it might object. "We have pictures. In the archive. My father says there were green places once, a long time ago, before the — " He stopped himself. Straightened up. Put his face back on. "It doesn't matter."

Before the what? Clara thought. But he'd shut the door on it, and she'd been travelling long enough to know when not to shove.

"It matters a bit," she said instead. "You're standing in the first forest you've ever seen. Most people would take a minute."

So he took a minute.

He walked between the trunks with his head back and his arms out, brushing his fingertips along the bark, breathing in air that smelled of rain and rot and living things. He found a fern and crouched over it for a long time. He picked up a leaf and turned it over twice and put it in his pocket. Something in his face had come loose that had been screwed down tight since the street, and he was — Clara realised, watching him — completely, ordinarily happy.

For about ninety seconds, the boy forgot everything.

Then he stopped.

She saw the exact moment it came back to him. It went across his face like a shadow crossing a field.

"My father," he said.

"Hey—"

He spun round, looking for the crack — for anything, a shimmer, a seam in the air — and there was nothing behind them but more trees, identical in every direction, and no way at all to tell which patch of empty forest they'd fallen out of.

"It was there. It was right there, it was—" His voice climbed. "Where is it? Where's the wall? It has to still be—"

"It's closed. It closed behind us."

"Then open it."

"I can't."

"He could." The boy's hands were shaking. He shoved them under his arms so she wouldn't see. "The man with you. He'd know how. And he's gone too, isn't he, so that's — so nobody knows. Nobody knows where they went and nobody knows how to follow and I was looking at leaves."

That last one came out badly. He heard it come out badly.

Clara crouched down so she wasn't standing over him.

"Listen to me. You didn't do anything wrong by being amazed at a tree." She waited until he looked at her. "And they're not gone. They went through the same crack we did, about four seconds ahead of us. That's all. Four seconds."

"Then why aren't they here?"

"Because those things don't put you down neatly, they just — put you down." She stood, and held out a hand. "Come on. Walking's better than standing."

He didn't take her hand, but he walked.

They went in the direction that seemed least like the others, which was the only method Clara had. The forest floor was soft. Somewhere above them, something was making a noise that was almost, but not quite, birdsong.

"So what was that?" the boy asked eventually. "That thing. The wall."

"A crack in time. In space and time, actually — the Doctor explained it and I understood about a third of it, which is a good day for me." She ducked under a branch. "It opens onto somewhere else. Anywhere else. And apparently it doesn't ask first."

"Where does it go?"

"Everywhere, from what I can tell. I came out of one on a rooftop in 1941 and ended up on your planet, so." She shrugged. "Your guess is as good as mine."

"That's not an answer."

"You sound like him."

The boy considered this and didn't seem to mind it.

"What do you think happened to them?" he said. "My father and your... " He hesitated. "What is he?"

"That," Clara said, "is a very good question, and nobody's got a proper answer to it yet, including him." She thought about it. "He's my friend. He's the cleverest person I've ever met and he's very bad at explaining himself, and if there's a way out of somewhere, he'll find it about four minutes before anyone else notices there's a problem. So — my honest guess? They came out somewhere. Maybe together. Maybe not. And he's already working on getting back."

"And if he isn't?"

"Then we find them ourselves." She said it lightly, which took some doing. "That's the job. It's mostly walking, if I'm honest."

They went on for a while.

"I don't know your name," Clara said. "I've just dragged you through a hole in the universe and I don't know your name. Bit rude of me."

The boy pushed a low branch out of his way and held it for her, which she thought was rather nicely done for someone who'd just lost his father.

"Davros," he said.

"Davros." Clara smiled at him. It was a nice name. She'd never heard it before. "I'm Clara."

And they kept walking, deeper into the trees.