Mal isn't sure about the new passenger they pick up on Cronos, but it's been months since Miranda, and they're starting to get low on supplies, and he offers to pay cash.

'Sides, Kaylee likes him. Mal thinks he looks suspicious, what with the bleached hair and the wicked eyebrow scar, and the coat that looks like it belongs in a museum. He watches from the shadows as Kaylee signs the newcomer on.

It isn't until Serenity leaves atmo, headed back into the Black with her cargo, that Mal meets their new passenger. He's in the kitchen making tea when Kaylee comes bouncing in, on her last leg of the tour.

"D'you like the paint in the kitchen? I painted it yellow on account of it's so cheery!" she says.

"It's pretty, luv," the passenger replies, amusement in his voice.

"We all eat together, and you're welcome to join us for meals." Kalyee catches sight of him. "Oh, and this here's our Cap'n, Mal Reynolds."

Mal turns around to face her. Her smile is bright enough to be her own sun.

"Cap'n, this here is Spike."

Mal doesn't have a chance to ponder what kind of a name Spike is, because the newcomer reacts instantly. He lunges for a knife that Janye has left on the table, brandishing it at Mal.

"You're not fooling me, Preacher Man," he snarls in his strange cockney accent. "I know what you are."

"Hey now," objects Mal, raising his hand in the universal gesture for 'friendlies'. "Let's just all calm down. If you're lookin' for Book, he ain't with us any more."

The double meaning of his words twists Mal's heart.

"Don't play games with me," Spike growls. "I'm wise to your game, Caleb."

"I don't know no Caleb," Mal says in his best calm-the-maniac-with-the-knife-down voice. "My name is Mal Reynolds, and I'm the captain of Serenity."

"She cut you in half, and you still come back." Spike is still brandishing the knife, and it's making Mal a mite nervous.

"I don't understand," whimpers Kaylee, ringing her hands in distress. "He weren't like this when he came onboard!"

Mal's face darkens, because not only has this piece of go-se threatened him, but he's made Kaylee scared, and that's an unforgivable crime.

"It's alright," says a calm voice from the doorway, and Mal thinks it's ironic that River is the one being calm in this situation.

"Stay outta this, Albatross," says Mal, not taking his eyes off the hostile with the knife, because all they need right now is for River to go all moon-brained on them.

"Put the knife down, William. He's not the evil you think."

Surprisingly, Spike lowers the knife.

"How do you know what I think?" he asks.

River taps the side of her head.

"You're shouting," she answers simply.

Spike regards Mal with narrowed eyes.

"He's not Caleb? Or the First?"

River shakes her head.

"The First isn't here, William. Your sacrifice endures."

Spike puts the knife casually back into the table, as if he had just picked it up to look at it, as if he hadn't been threatening Mal with it just a second before.

Mal darts forward and snatches the knife away. Can't leave a weapon lying around with a madman on the loose. Spike doesn't seem to notice.

"Sorry, mate," he says. "You're a dead ringer for someone I used to know."

"And not like very much," Mal says dryly, stowing the knife in his belt, just in case.

Spike regards River with open curiosity, his gaze seeming to guess too much about her. It makes Mal worried again.

"Your girl a seer?" he asks bluntly.

Mal opens his mouth to deny it, but to his surprise, River nods.

Spike nods back.

"I've known a few in my time," he says casually.

By now the rest of the crew has gathered in the kitchen. It's been too quiet since Miranda, and this is the first entertainment they've had in months.

"Someone killing the Cap'n?" Jayne asks excitedly.

Simon steps forward.

"River…" he says, in his best placidating voice. "Are you bothering our passenger?"

River shoots him a look that clearly says you are a boob, and ignores him.

"William won't hurt anyone," she tells the room.

"You don't know him," Simon argues, ever the protective brother.

River smiles, a rare genuine smile that lights up her young face.

"I can see his soul," she says. "It's singing to me."

"Thought you said your name was Spike," Zoe cuts in. "She called you William"

"Well, yeah," says Spike, leaning casually against the far wall. "Spike's a nickname. Haven't gone by William in a couple a' hundred years, pet," he says to River.

"It's who you are," says River simply. "I'm River, you're William." She walks forward, ignoring Simon's worried gaze, and reaches out to put her hand flat against Spike's chest. "How long as his been? 500 years?"

"More like 6," says Spike, and there's a deep sadness in his voice.

"Now I'm confused," Inara says. "Did you say 600 years?"

"I'm confused my own self," says Mal, cutting in. "600 years of what exactly?"

"Living," says Spike, pulling a cigarette out of his pocket and lighting it. The sharp smell of tobacco fills the room. Simon frowns. "Or rather, not living. Whatever you call what I'm doing."

"You're 600 years old?" Inara asks in her beautiful voice.

Spike shrugs.

"Give or take."

"You look good for your age," Inara says dryly.

Spike leers.

"Back atcha, luv."

The way he is looking at Inara, like she was something to eat, makes Mal's blood boil. But before he can rough this strange man up a little for looking at Inara that way, River speaks.

"You're a champion," she says.

Spike chuckles humourlessly, taking a drag from his cigarette.

"Fat lot of good that's done me. Thousand years of peace is half over. Everyone's forgotten about champions."

"I haven't," River says. "I heard you."

"Yeah, but you're a seer, aren't you, pet?"

"What do you know about my sister?" Simon demands, looking scared.

Spike shrugs.

"I understand a bit about seers. Was with one for a hundred years or so."

River adopts a strange sing-song voice, the accent close to Spike's own cockney.

"I've been naming all the stars. But I have them all the same name, and there's terrible confusion."

A muscle in Spike's cheek twitches.

"That's the one," he says. "My Drusilla."

"She's dead," River states.

Spike nods.

"By my own hand. Had to. Couldn't let her go on the way she did. My poor Dru. But it has some poetry, doesn't it? That I was the one to do it. Circle of life and all that," he gives a humourless laugh.

"Poor puppet on broken strings," says River. "Didn't get to be a real boy." She stands on her tip toes, craning her neck so that she can look straight into Spike's piercing blue eyes. "Has to keep going. Doesn't get to rest until his task is done."

"Something like that," says Spike. He throws his cigarette on the ground, and crushes it with his heel, much to Mal's disapproval. "If you know anything about my task, pet, tell me now."

"Don't have that connection," River admits regretfully. "Only know what I hear. Only hear when I listen. Try not to listen. Hurts too much to hear people's blackness."

"S'alright, luv," Spike says, looking disappointed. "Didn't expect it to be that easy."

Mal is getting frustrated with the riddles. River's being more moon-brained than usual, and his patience has come to its end.

"Someone had better ruttin' explain what's goin' on," he growls. "Or I'm going to start to get a mite testy."

River cocks her head to one side, as if she's listening to something. Then, she smiles that radiant smile again, the one Mal hasn't seen on her face for a long time before today.

"William's here to help me understand," she says, turning to him.

"Understand what?" Kaylee asks.

River doesn't answer. Instead, she looks at Spike appraisingly, and then throws a punch at him. Mal starts forward to interfere, to stop River from hurting Spike, because Buddah knows she can take anyone apart in under two minutes. But Spike surprises him once again. The bleached blond dodges reflexively, and throws a punch of his own. For a moment they are a blur of limbs in the cramped space. Then, just as suddenly as it starts, the fight is over. 90-pound River has thrown the tall Spike onto the table, leaning half over him, her fist balled just over his heart.

"Gotcha," she says.

Spike's eyes are wide with surprise.

"You bloody woman! You didn't tell me you were a slayer!"

"Didn't ask," River replies, moving her weight off him.

Spike stands up, brushing himself off.

"What is it with me and slayers?" he asks, shaking his head.

"Will you help me?" River asks.

Spike stares at her for a long time. Then, he glances at the ceiling.

"Training another slayer?" he asks nobody in particular. "That's my task? You'd think they'd come up with something original."

"In every generation there is a chosen one," says River in a sing-song voice. "Only she can stand against the forces of evil."

"Not the way it works any more, luv," says Spike. "There's lots of ya now. But you must be special, if the Higher Powers want you trained proper. Never heard of a seer-slayer before."

"I'm special," says River proudly, drawing herself up to her full height. She doesn't even come past Spike's shoulder.

He chuckles.

"Sure you are, Little Bit. Alright, I'll take the job."

River pulls out at chair at the table, and primly sits on it.

"I'm ready for my first lesson," she says.

Spike smiles, a gentle, genuine smile.

"Alright. We'll start right away. First lesson is: don't die."