Title: The finish line's a good place we could start
Characters/Pairings: Daniel, Eloise, Charlotte, Theresa (slight Dan/Theresa, Dan/Charlotte)
Rating: T
Summary: He will do this a thousand times, fail a thousand times.
Spoilers/Warnings: Up to 5x14; character death.
Disclaimer: Not mine.
A/N: Written for Livejournal's Spooky Lost Fic Battle and the prompt of Daniel, the butterfly effect. Title from Snow Patrol.

----

A shot cracks through the air.

(This is all it takes.)

----

Daniel learns early that sometimes one thing can mean something different entirely, or maybe (and this will come much, much later, when it's far too late) nothing at all.

He reads, in a pilfered science journal, about chaos theory -- a butterfly flaps its wings in Brazil and sets off a tornado in Texas -- and that's dumb, he'd muttered, secure in his eight-year-old knowledge of the world, scribbling harder in his notebook and pouring over math equations. Doesn't make sense.

It's cause and effect, his mother had replied, clutching her teacup with bone-white fingers, face drawn grim. Everything means something, in the end.

----

Later, he comes to this -- small variations of the initial condition of a dynamical system may produce large variations in the long-term behaviour of the system.

It's quantum mechanics, his favourite university class, and each line in his journal -- each scratched-out equation and scribbled note; lines and pages blotted with ink -- brings him closer. To what, he isn't quite sure.

(Daniel can't help but wonder what's been left behind in its stead.)

----

He will do this a thousand times, fail a thousand times, memory like a drifting haze -- sees the end at the beginning (jungle dirt beneath his knees, a pair of faces -- blond hair; dark, olive skin -- swimming in front of his eyes) and what happened? Theresa asks, worry pinching her expression.

Nothing, he snaps, stripping off his vest and already halfway to the chalkboard. The effect's exponential; impossible to forecast. I just -- I need to get back.

It never changes -- whatever happened, happened; he will remember this, always, when words and faces and feelings fail -- and when the forgetting comes, he can almost believe it's a blessing.

----

She gets better and then she gets worse; a moment of lucidity -- her voice cracks, dusky with strain, disuse.

Why, Dan? Her tears cut a swath through the blood, dribble down her chin. Why is this happening to me?

Because, he murmurs -- and he thanks something, anything, that Theresa's already slipped away again, too soon to hear his words --

-- it has to.

It always does.

----

He forgets her name more often than not (Theresa, trembling just out of reach), still sees a pale-haired, dark-eyed figure on the edge of his vision most nights in the silent, too-big Essex house. Every piece of him feels cracked, rough around the edges, full of splinters and shards.

The footage on TV makes him weep (Caroline worries more than usual, ups his meds) and get on the freighter, his mother tells him; something deep inside quirks, quivers -- you should know this -- but he goes anyway.

(No matter what, I'll always love you.)

He would trade the whole universe to be what she wanted, after all.

----

In the end, it's Charlotte that pulls him together -- quarks and molecules and atoms drifting and then tendered, back into his core, more than any island or miraculous cure. (I know you, he half-whispers, hypnotized, often enough to make her laugh, like it's some joke between them, chalk it up to academic connections and never think twice.)

Her hand at his brow feels like baptism (I could change it, he considers, though he doesn't know why, cause and effort; where did this all begin?) and he swears he hears a flurry of wings, light and fast, in his ear.

"Dan, you okay?"

She smiles and it burns through him, blushes and rakes fingers through his hair, wanting to grab her hand, press her palm to his chest and say, fix this, please. Because he thinks, deep down, that maybe -- just maybe -- he could do it, change it, for her.

----

Charlotte dies.

(Over and over and over.)

He can't save her.

(He promises anyway.)

----

Ann Arbor is hell -- like a waking nightmare -- but then something changes.

A big enough variation -- Dr. Chang eyes him with mingled distaste and mistrust, storms back into the Orchid and waves off his advances, Miles, furious, barely speaks to him on the ride back to the barracks, Jack's trapped tight at destiny.

It's all in motion (he imagines particles of air over waves, over blue-green waters, gathering speed, momentum; shifting and changing and building) and then he's the rushing the Hostiles' camp, Richard in front of him with arms raised, his mother nowhere in sight --

A shot cracks through the air.

----

(This is all there ever was.)