Disclaimer: I don't own CSI, although I'm beginning to think that CSI owns me.

She's been watching him work his cases and she wonders if anything could have happened between them. She's been like this since that disastrous attempt to ask Grissom on a date. Sara is always wondering what would have happened if she'd chosen a different man to become obsessed with. Today, it's Warrick Brown.

They're a study in opposites.

She's known it since the day she realized he'd only entered a casino on company time to post bail for a kid, and she realized it again the day she saw his eyes melt over a baby, born in a world far too complicated for such innocence.

She jumps to conclusions that anyone would be hard-pressed to contradict, while he seems to want to reserve judgment. It's like he wants to believe the best in people, despite all they see. She's always been content to assume the worst. She knows her harsh judgments aren't always correct, or very scientific. They've even hurt Warrick in the past, but she's never been one for changing her ways.

She supposes they each get too involved in their cases sometimes, but while he storms around, looking for someone to scream at, she shuts herself off from everyone and convinces herself she is the only one who can bring justice to the victim in the morgue.

She is set in her ways. She'll learn the new technologies to keep her job, but she likes things just so. He'll never stop seeking the latest forensics toy, or pushing Grissom to invest just a few thousand more dollars in gadgets to catch the bad guys.

They've always interacted with a kind of intensity that could translate well into a relationship, or at least a decent string of one-night stands. But she knows that while she has no problem forgetting personal ties just so she can forget everything else, he wouldn't let her make him into another fruitless escape.

She drinks her pain and keeps it with her always; he puts a value on his and bets it all, hoping to turn his suffering into something tangible. That way, if he loses everything, at least it's gone. She doesn't understand how he could look at such awful odds and keep up hope, while he doesn't see how stewing in agony will ever ease old wounds.

She's all about hiding what she feels, and if she's ever feeling anything at all, everyone around her is forced to guess why. He's the most up-front person she's ever met, and he'll get right in her face about anything that's on his mind.

She's haunted by ghosts and a traumatic past. He's haunted by insecurity and the hope that this time, his gamble will finally pay off.

She's pale. She sometimes wishes to be invisible and transparent, so that she won't have to pretend anymore. He's dark. He only ever wants to be seen, so that they'll finally believe he can be all he hopes for.

She lies to herself. She rationalizes one more drink, because surely it will be the one that finally fills her up. He's only ever honest, because he's lied to himself before, and nothing good ever comes of it.

They've been colleagues, enemies, cautious friends. She's seen him shirtless, throwing phone books across the room, shouting at his boss. He's seen her at her weakest, at her most determined, at her most ruthless. She doesn't love him, but she'd like to think she could.

She's always afraid. He never stops striving, and that takes a lot of courage.

She gets so defeated that she sometimes can't make it out of bed without a drink. He refuses to let the job kill him, and so he gets enough sleep, keeps a strict routine, and shows the LVPD that he will not fail them.

She knows you can't choose who you fall in love with, but she thinks that Warrick Brown would have been a good choice. He's patient enough to put up with her, damaged enough to tolerate her imperfections, and charming enough for her to replace Grissom with. But she also knows they're just too different. Opposites may attract with magnets and basic physics, but Sara knows herself too well to be optimistic.

He's steady, he's intense, and he needs someone who can keep up with him. She'll never be that, not for anyone.

She can function, but she thinks she stopped truly living years ago. He's a survivor. She never did have that kind of strength. She thinks maybe that's why she'll never love him. Maybe that's why she sometimes hates him so much.

A/N: I'm not entirely happy with this, but I don't have a beta, so it's the best I could come up with. Reviews are greatly appreciated!