***

River knows that Miranda wasn't the only secret they had.

It was the big one, the one hammering its way out of their skulls and into hers. But there were others. One of the officials who'd toured the facility had been far more intent on something else. She'd felt it in him. She'd seen it.

River closes her eyes and sees again now the memory of someone else's memory. Arms outstretched in front of her as if they were her own. Masculine hands that hold up a thick, matte-black binder on a polished wooden table. The hands page through the heavy report, an official whitepaper. Formulas, equations, schematics, all supporting a central theory.

It's only now, two months after they loosed Miranda's secrets on the world, that River has the time and the clarity of thought to consider the memories of these other secrets. Like the black binder. She knows it's terribly important, but she can't remember why.

Two whole months, as roughly and archaically calculated by the synodic period of old Earth's solitary moon. Two months, and Zoë still avoids her without being obvious about it. She's grateful for that. Hard enough to be on the ship with her because--

Because--

River tries to shut it out, the memory of the first full blow of Zoë's grief. Wash was dead because of the Reavers and cosmic bad luck. And Zoë had cast one venomous look at River as they'd prepared to hold the line; a single thought, laced with hatred:

You knew. Didn't you?

River had known. At least in an abstract way. She'd known he was dead before it happened. But it had been just another horror she couldn't push away. And it was too hard, back then, to separate the knowing from the nightmares.

And it had been nothing compared to the finality of the fact itself, experiencing it in realtime. The worst part the realization that Zoë would never turn loose of her agony, never speak of it, never allow herself any closure or the normal stages of grieving. She would keep it coiled tightly inside her forever. Because that was Zoë's way. That was how Zoë made the universe a thing she could compass and accept. It was the only way she knew.

Career military. Discipline. Control. Limits, boundaries, orders. Chain of command...

Top secret clearance.

Back on the other track now. The binder. River concentrates. She sees the pages in front of her eyes again. She understands the math, as far as it goes, but she still can't get the big picture, what purpose it all serves. The man hadn't understood all of it himself. He was a politician, an executive, not a scientist. Maddeningly, he'd skipped pages. And yet his mind was more disciplined than the others; they'd all silently screamed out the secrets of Miranda at her, but this man had just carried the images of the binder, burning away in his head without implication.

River senses Simon approaching, but she doesn't open her eyes. He touches her arm, speaks words to her. Simon moves lately within a small storm of thoughts and feelings that are mostly of Kaylee: the hours they spent in his bunk last night and the night before, and the hours they'll spend there tonight.

Warmth, skin and softer skin. Profound relief, like rain after drought. The slow giving of ground to Kaylee's easygoing and uninhibited ways...

Focus. Focus.

Simon persists, faithfully reprising the role of the concerned brother. He tells her she should eat.

She sighs long and deeply. Eyes still closed. Numbers and symbols float tantalizing, just out of reach, out of her ability to distill them into meaning. They morph in her vision and become ancient runes.

Sigils...vèvès...glyphs.

"'Any sufficiently advanced technology is indistinguishable from magic,'" she mutters.

And after a while, Simon goes away again.

River doesn't move for hours. By then it's nighttime, ship's time, and most of the crew are in their quarters. But night is even worse for her; people no longer focused on the day's duties, their thoughts and feelings flowing more freely, their conscious and subconscious minds closer together than any other waking time.

Her mind wanders through Serenity.

Kaylee and Simon, in Simon's narrow little bunk. Kaylee's on top. Simon looks, as always, just a little bit stunned. River giggles to herself.

Mal and Inara, each at opposite ends of the ship, but each thinking of the other. Achingly. Both of them in love with the ache, that's their problem. In love with their unrequited love. The ridiculous and the sublime. It's worth a giggle too.

And Zoë--

It all turns dark, like it always does. Simon and Kaylee, two different worlds, two different minds, too different. Mal and Inara, forever locked together in their bittersweet futility, doomed to hold out and hold out until it's all too late, not realizing that time is finite, that time will shut the book on them and they'll never know how it could have been.

And Zoë--

River recoils, puts her hands to her head, squeezes her eyes tightly shut. But it never works. It never blocks out anything.

Alone. Dark. He's gone, just an empty space in the bed next to her. Empty forever, she'll keep it that way this time. Alone forever and ever...

River whimpers.

After a moment, she gets up and flees to the only place that ever offers any refuge.

"They all make such a racket," she says plaintively, and Jayne understands as much as he needs to.

He cleans his guns endlessly, obsessively; sharpens his knives, all because it keeps him from having to think. He seems to know that River doesn't have that luxury.

River sighs and breathes in the silence.

***

Hours later still, everyone is asleep; even Mal, she knows, has nodded off on the bridge. River sits on the floor in a corner of Jayne's berth, her knees tucked up to her chest, arms wrapped around them. The chill of the metal deck burns into her bare feet, but she ignores it.

She tries again. Dives into the memory of the memory.

The wooden table is of real oak. She knows it's indigenous to Earth-that-Was, a botanical legacy that's traveled with humanity from star to star. But it's not relevant. The binder is heavy, its contents big enough and important enough to be entrusted to hard-copy in their entirety. Sometimes the old-fashioned form-factors are best. She knows without seeing them that there are two armed guards outside the door of the room where the man sits at the oaken table with the binder.

The hands page through the document again. She's seen it all before.

But this time, River catches a new flicker of memory: the fingers flip back to the first page just before closing the binder. It's just long enough for her to see the title, printed in plain boldface. Absurd in its nonchalance.

It all makes sense now, what she's been seeing. Why it's important. Her eyes fly open, but the words remain in her vision as though the letters were made of fire.

"Temporal Displacement Theory," she whispers. And smiles in the dark.

***

It's hard to communicate specific instructions to the others. It's hard to rein in the floating edges of her thoughts and compress everything down to a size and speed and shape they can understand.

She starts with Kaylee. She draws the schematics from memory. It's not a big device. It doesn't require any rare metals or controlled substances or enormous power sources. In fact, it's disturbingly simple.

Simplicity...elegance of design...Einstein...

Simple, like Kaylee's needs and desires. Elegant, like her intuitive understanding of machinery. Kaylee and Simon aren't that different after all. Born to fix things. And people.

"He wanted you for a long time," River says, for a moment entirely distracted by this alternate track, pulled into Kaylee's ambient thoughts.

Kaylee stares at her, and River remembers that people like to discover these things on their own.

"It's not important," River says. "Not right now. But ultimately..." Hard as it is to communicate, it's harder to retrace her steps in the conversation and find the place where she left the other person. "Ultimately, it's all important in its own way."

Humans are social animals. They need companionship. They need happiness. At least once in a while. Isn't that why I'm doing this?

Focus. Kaylee's made no comment. River pulls her attention back to the schematics. "Can you build it?"

"Sure," says Kaylee. "I'll just need to pick up a few things at the next port. But..." she frowns at a page of diagrams. "What is it?"

"It's not a weapon," River says quickly.

"I--I didn't think it was," says Kaylee. "I just don't understand exactly what I'm lookin' at."

"It's a surprise," says River finally. But that's not the truth. Because if this works, if the math's right, it won't be a surprise at all. Because no one will ever even know she did it.

The other part should be harder, but it turns out to be easy.

"We have to go back," she says to Mal as they sit on the bridge that night, just the two of them. "We have to go back," she repeats. Fewer words are better. Small words. Compression of information. "To Mr. Universe's place. As soon as we can."

Of course, soon is relative. But it's not worth explaining that.

"And what in the name of all that's unholy would I want to go and do that for?" Mal's not really paying attention to her, looking at the stars, looking for whatever it is he hopes to see out there.

She can't explain it to him. Technically, he'd never understand. Generally, he'd never believe her.

"Trust," she says, experimentally. "That's what I'm asking. I'm asking you...to trust me."

The words sound as alien to her as they must to him. But she's got his full attention now.

"Trust you," he echoes.

She nods. He's done it before, at least once. But that's hardly an empirical argument in favor of it.

He shrugs. "Oh, what the hell."

***

Weeks pass. She notes the passage of time with more interest than usual.

Kaylee finishes the device after a layover at Emory. She doesn't tell anyone about it. River knows she's kept the secret.

She worries, even though the math doesn't support it, that the universe will somehow try to balance itself out. That it will demand a blood sacrifice for her hubris.

"But that's just superstition," she says aloud. "Mythology. Conclusions drawn on insufficient data. Intuiting patterns out of the chaos where none exist. And the paradox issue is completely avoided in this model..."

Mal eyes her.

She stares back. "There is no monster under the bed," she says, with absolute conviction.

"Seems to me you'd know better'n most of us," Mal mutters.

When she gives Mal the final coordinates, he frowns. "This ain't the right heading for landing." He punches the numbers up a second time. "It's not far off, but nary a thing at these numbers but empty space."

"I know," she says. "It's where we were. Or a close enough approximation. Degrees of flexibility in the system..."

Orbital mechanics...absolute position...expanding universe...

The crew doesn't even know they're here. Everyone's asleep. No idea what's about to happen. And Mal, for whatever reason, is still operating on trust.

So he's rediscovered belief. Will he ever forgive any of us for that?

When the ship is in position, she makes a final check of the settings on the little device that Kaylee assembled for her, now strapped to her left wrist.

"I have to go now," she says to Mal, standing up. "But we'll see each other again soon." She pauses. "Relatively speaking."

River takes a breath and punches the execute button before Mal can say a word.

There's no wormhole, no feeling of travel or movement, no sense of interstitial time passing. One second she's standing there with Mal on a peaceful, quiet bridge. The next blink it's chaos; noise and gravity and falling. She's strapped into her chair, back in the common room.

Just like before.

She rips off her seatbelt and runs headlong for the bridge. Trying not to fall, not to get slammed into the walls as the ship plummets.

She bursts onto the bridge. The same bridge she shared with Mal a moment ago, except everything's different.

For one thing, it's nearly three months earlier. A glance at the chronometer on the instrument panel tells her that.

For another, Wash is there. Alive.

"It worked," she whispers.

Fighting their descent into a gravity well, his arms strung out like steel cables, Wash doesn't seem to register her sudden appearance on the bridge. But Mal does. He double-takes, yells, "River, what the hell...Jayne!"

She's done the math a dozen times. She's practiced, acted it out on the bridge alone at night. Studied the ship's logs and telemetry to the millisecond. Wash has to land the ship. His hands can't leave the controls until they come to a full stop. She's done the math until her head aches, and she knows this is true. Wash has to be the one to bring the ship in, or they're all dead anyway.

But it only leaves her a few precious seconds in between.

Falling still. Spinning. G-forces dragging the blood to the back of her brain. She nearly goes flying back against the bulkhead, catches herself against the edge of the co-pilot's chair. Everyone else is strapped in. Mal is still staring at her; Jayne's voice echoes over the com, panicky, incoherent. "...she was here, cap'n, and then I swear she just disappeared!"

River grins. No one can exist in two places at once, Jayne. Not even me. It doesn't work like that.

Sudden impact, and she falls to the deck, her feet and breath knocked from her.

A gasp after air. Focus. Follow the drill. Like we rehearsed. Get up on your hands and knees. Crawl over behind the pilot's seat. Grab onto the back of it. Close to Wash as possible. Crouch down near the deck. Get your head down. Hang on, with all the strength you have.

While they fall and jerk and spin, and the ship's internal gravity tries desperately to keep down oriented to down and to keep them all from losing consciousness or breaking their necks.

Another impact, thudding through her bones. The long slide she remembers, pieces of Serenity being ripped off, left behind. Serenity is wounded. The scream of metal. And a final skidding, shuddering stop.

Only enough time for a single breath, then:

"Five," she says aloud. She loosens her deathgrip on the back of the pilot's seat and rises. She's dizzy with adrenaline and her arms are rubbery, but she springs forward, dives around in front of Wash. "Four," she chants.

Wash, coming out of the hyperfocus of piloting, struggles for words. "Where did you--"

"Three!" she shouts, interrupting him, fingers fighting with the straps that secure him to the pilot's chair, jabbing desperately at the fasteners.

Wash stares down at the movement of her frantic hands, mystified. Zoë and Mal just sit there also, breathing, in shock. "River!" Mal finally yells.

"Two," she gasps. The last strap comes free. She grabs Wash by both arms and hauls on him as hard as she can, yanking him down to the metal deckplates with her. Mal is cursing up a steady steam of Cantonese now.

"One," she says softly, and watches with dreamy fascination as the spiked projection of the Reaver ship impales the empty pilot's chair.

***

"They were afraid of it," she says to Wash conversationally, as they wait for the Reavers to break down the first set of section-doors. "They were afraid of the monster under the bed. They destroyed all the research in the end. But it's all in here." She points to her head. "Besides, seven isn't really a lucky number," she says. "Eight is better."

"Yes, well, I don't doubt any of that," says Wash. "But you might want to get behind Jayne now. Or, you know, grab a weapon..."

Grab a weapon. River laughs and laughs.

And prepares to re-live the last few months of her life.

Because that was the way it worked. No alternate realities created, no meeting oneself or destroying the very fabric of time and space, like in those old, old science-fiction books. Just a one-way ticket backwards. A cut-and-paste, clean and elegant. And one small change, as far as the universe was concerned.

"In this case, it turns out the butterfly effect is minimal at best," she says, and bursts into giggles again.

Pivotal moments she'd been physically and temporally present for, that was all she could alter. And there were other things she might've tried to change. But looking back through time, she found there wasn't much else she wanted to change. She couldn't have saved Shepherd Book; she just hadn't been there, and couldn't be. Because if she tried to go too far back, tried to change what had been done to her by the Alliance, tried to stop her role in the entire chain of events from the beginning...then all the souls lost on Miranda would remain lost, unknown, unremembered. It was too great a responsibility to shun.

She knew Book, of all people, would understand. And everything, she was convinced, had happened exactly the way it was supposed to. Including this.

She looks around. They have no idea what she's done. Zoë hands Wash a gun, flashes him the special smile she never shows to anyone else. Jayne is arranging ammunition. Kaylee and Simon speak to each other softly. No one notices her, or the device strapped to her wrist. And now she takes it off, crushes it beneath her boot-heel. No idea at all. They think it was just her usual prescience, her showing up on the bridge in the nick of time to save Wash.

The Reavers are howling, tearing down the doors. River shakes out her muscles, balances on the balls of her feet, feels the adrenaline surge. But it's not nearly as scary this time.

"It's my turn," she says, after a long interlude of shooting. "Again."

***

END