But science, spurred on by its energetic notions, approaches irresistibly those outer limits where the optimism in its logic must collapse... – Friedrich Nietzsche

The wasteland makes her lips dry and her hair fall limp on her shoulders. She tightens the plaid jacket at her chest, buffeted by the wasteland wind, so hollow and full of ghosts.

She can't bear to watch him, not directly. She perches on a sprawling plank and listens to him ramble under his breath, and she tries not to cry.

All the vortexes of time and the suicide runs and the obliterated homeworld never drove him to madness like this.

Out of the corner of her eye, she sees him whirl in circles, creating little dust devils that crawl up his tattered tweed pants. The sonic screwdriver sputters on and off. The long fingers of his left hand search the grain of the factory's charred walls.

"It's something about the polarity, something-something-something-aHA! No, no, that's not it at all, it's rather a larger problem—perhaps they've all been abducted. Abducted! Of course! Burned and abducted! Amy!"

He bounds out of what used to be the lunch room, kicking a can in front of him like a soccer ball. Planting his hands on either side of her, he blinks too close into her face.

"Now, what could have abducted the Earth's entire population at once. Riddle me that, Amelia Pond."

"Doctor…" Her voice cracks. She claws at her throat. "I need water."

"Of course. Of course. I'm sorry. I'm so—" He frowns, opens his cracked lips as if tasting the words. "I'm so sorry." He tosses his head. Amy can almost see the dangerous thought catch on the wind and carry away. "There's a bottle in the TARDIS on the…the thing. The blue thing, the light-up thing, the—oh, never mind, I'll show you."

He takes her hand. She recoils. His skin is cold and rough; it isn't him at all. She sees him calculate her hesitation, cogs and wires behind his eyes. There is a blue fire in his gaze.

"Amy."

"Doctor," she can just whisper.

"Get up. Now."

She has heard that tone before—commanding her to stay when the Angels surrounded her; challenging a sky full of his century-old enemies; making Rory decide between his woman and his wife. She cringes, and he sees it, and the madness goes somewhere deeper to lurk and wait.

He crouches down in front of her and crooks his finger under her chin. "Oh, look at you—beautiful Amy, look what this place has done to you."

"Look what it's done to you," she croaks back.

He stumbles back and sits down, hard, patting his face, his hair, his chest. He stares at her.

"I've gone mad, haven't I," he says.

She doesn't nod. She looks away, shivering and hugging herself. Scudding clouds gather, arranging a thunderstorm.

They are quiet for a while, listening to their own heartbeats, to the wind, to anything but their thoughts. The purr of rain on metal rooftops starts in the distance.

"They're gone. They're all gone," the Doctor says at last. "The human race, burned before their time, and I got here a moment too late."

"We did," Amy says, swinging herself off her board. Her anger tingles in the tips of her fingers, and she flings her arms into the air. "I wanted to circle the Singing Forests one last time. You didn't want to yell at River to get out of the pool. And now…" She takes a deep breath; the air scorches her insides. "Now we've lost them all."

"It's killing me." He stares at the ash slowly covering the sonic as the wind piles it, obscuring the silver gleam. "This madness. I can feel my hearts…well, I suppose they're breaking." Clutching at his chest, he heaves himself onto his feet.

Amy gazes up into his face as he comes to stand beside her, and she leans against him when he drapes an arm over her shoulder. His is the only warmth as they take a step forward, then two. Then the rain hits them, and they are soaked through, holding on to one another because there is no one else.