By the rivers dark
In a wounded dawn
I live my life
In Babylon

Prologue

She kills the first Tuvok who shows up on her doorstep.

Incredibly, they send another.

Kathryn doesn't need voice authentication and blood screenings to know it's not him. But when the first imposter doesn't revert to a liquid form, something settles into the pit of her stomach, roiling and dark. The Doctor would be able to tell her what she's looking at without starting a panic; when she tries to reach him, she's cut off. Her screen goes dark.

She packs. Where can she go? She should avoid transporters, she thinks, where her DNA could be tracked across the planet. If Tuvok is compromised, then Tom is closest. She hasn't seen him since the reunion but he'll help her, if—instinctively, her mind tries to dart away from the thought—if he's alive, if he's still him. She could take the ferry to Sausalito, save an hour, but if they're looking for her… which means she can't cut through campus, either.

She'll wait until dusk, cross the bridge in the dark. Just a few hours away. She tugs on a dark grey sweater and weatherproof boots. She paces, her ears straining against the April rain pummeling her skylights. What else? Weapon, rations. It's ridiculous, but—she takes her old communicator out of her desk drawer and tosses it into her bag. She'll leave the other behind. She doesn't know enough to guess how far this goes.

She knows enough to be afraid.

She knows enough to run, when the doorbell next echoes through her home.

By the time she makes it to Tom's she is soaked to the bone, the gloved hand that grips her phaser cramped and aching. She approaches carefully, silent except for her chattering teeth, skirting the side of his small house. She pauses beside a window, listening. That all seems quiet inside tells her very little, considering it is three in the morning. She takes two more steps toward his front door and she must trip something, because a light comes on and then Tom is there, eyes hard and a phaser leveled at her chest.

"It's me, Tom," she tells him, not lowering her own weapon.

"How do I know that?"

"I don't know." If she offers to cut her palm, show him her blood, and he knows what she knows, then he'll think she's trying to deceive him. If she doesn't make the offer, he may think it anyway. Everything they thought would keep them safe is worthless. Helplessly, she says, "Ask me something only I would know."

Because there are any number of questions he could choose, things no Changeling interrogator would think to extract from her before assuming her form, things they'd kept out of their logs all those years ago. He could ask her about the Billings, after the Billings. He could ask how he once convinced her not to consign the last dregs of a civilization to death for the crime of taking him hostage.

"Your surname," he says. "Tell me your surname."

An incredulous laugh bubbles out of her, closer to hysteria than she likes, and she covers her mouth with one tremulous hand. She drops the phaser.

"Paris. It's Paris," she gasps, unaware until just this moment how sure she'd been that she would come all this way just to find him gone, replaced, and although he's right in front of her a vision of his broken body dances in her mind's eye and she thinks, Tuvok, then forces herself not to, not yet.

His long legs cross the expanse of lawn between them and then he's folding her into his arms, tucking her head under his chin, and it's like her lungs have just remembered how to take in air for the first time all day; she lets out a shuddering breath, steadying herself, sinking into him.

"Let's get inside," he says, finally. "Something tells me we have a lot to talk about."