t's a lie, what they say about life flashing before a dying person's eyes. River should know, after all; she's done it twice. Not that it lasted long, but that's twice more than anyone still walking around. Except for him, and she doesn't have to tell him it's a lie.

But this time, as she splices wires and adjusts circuits, she thinks it's more like the last piece of a puzzle, the center that defines the whole picture finally complete. So, this is how she dies. No wonder he never told her.

One of the risks of a nonlinear relationship, of course—seeing your spouse die and meeting again. She'd become so used to his clumsy ways, his childish exuberance, that she assumed he'd be there for the beginning as well as the end—his beginning, her end. But this regeneration—so somber, so anxious—she can't tease him, and not just because he doesn't know her. Too many ghosts.

But she was his ghost all along. At first, when she was mostly Mels, she only recognized anger, pain and fear, the emotions of prey before the predator. In Utah, she wasn't really concerned with him—oh, she deluded herself into thinking of it as a grand romantic gesture, but it was really seething rage against her captures, refusal to be their clever weapon any longer.

She'd had a lot of time to think in StormCage, though—twelve thousand consecutive life sentences, after all. On the nights the TARDIS hadn't materialized into her cell or she hadn't decided to test a new toy by breaking out again, she'd run her fingers over the blue diary and let her mind wander. He trusted her—that food for thought lasted a year, with thoughts of her parents reserved for the weekends. Only on the nights when the rain had stopped and the light of a strange sun created rainbows outside her window—the nights when beauty ached more than any loneliness—only then did she muse on the strange, wonderful words he whispered for River.

One night, maybe seven years into it her sentence, he took her out for what was supposed to be a quiet night, sitting above the plane Persephone at one-tenth of one-percent the spend of light, watching as it was terraformed from barren rock to lush jungles and rich oceans. But the Azeerlits (a highly evolved form of obligate anaerobes) had their own plans for the planet, and, as usual, the Doctor and River got trapped in the middle—quite literally, the anaerobes replaced the outer oxygen tanks with a sulfide compound and they ended up having to crawl through the dispersion shafts to escape.

The shafts had fans. Big, fast ones with serrated edges.

She doesn't remember much after that—heavy breathing, being helped (certainly not carried) back to the TARDIS, four weeks in the StormCage infirmary hooked up to lots of wires that beepbeepbeeped when her hearts' rate dropped. There were presents—one, sometimes two or three a day, wrapped in brilliant blue paper without a signature. A blouse to replace the one she'd been wearing—even the 51st century hasn't mastered getting blood out of clothes. A box of jammey dodgers, fresh from Marks & Spencers. A jeweled egg made for the last Russian czar.

"You won't die now," he'd whispered. "You can't." In the moment, she'd taken it for encouragement. But during those weeks, she'd analyzed his tone, the furrows where his eyebrows would be. It had sounded, for all the world, like a fact.

So she watched and listened and thought. She can't say when she first knew, any more than the moment sunset begins on a stormy day. But the thought grew clearer and clear in her mind, though she'd never say it aloud. He knows when I die. And, later, he's seen me die.

She's never asked him to confirm it. She didn't tell him about Utah; let him keep this one spoiler, the ending he's known for decades, if not centuries. No wonder it's her catchphrase. When you read a book back-to-front, the conclusion is never in doubt, just the motives.

River glances down at him, handcuffed to a pole. Yes, it always ends this way. She'd been the one who gave Amy those handcuffs, after all. And then accidentally-on-purpose lost the keys. This might even be the same pair, for all she knows.

He fidgets; time's running out. This is his entry point on the Mobius strip of their lives. But she's broken through the fragile loop, falling into darkness.