A/N: Inspired by a quote form Joss Whedon in which he said Jayne is smarter than he lets on. Takes place before the movie. Obvious AU. I don't own anything except Mattie, and technically, she's not mine either. Mattie is mention in the episode The Message, when Jayne is reading a letter from his mom. In the series, she's nothing but a name, mentioned in one line, saying that she's sick. I sorta ran with it, making my own story about her, and I don't know how to explain that any better. I've had second thoughts about, think I should make her a completely, 100 percent original character, but I decided to be bold. Please review!

"Today's the day I'm leaving. I'm not running away from home. I like to think of it as running to something. I've been sick awhile, but I'm better now. Nobody from the Academy has come looking for me yet, but I want to be long gone before they do. I know you don't believe they really let me out for holiday, and especially not for 4 months. I know their coming for me soon. So, call it selfish, but I'm running. I'm going to join my brother in his travels. I'm tired of the rock and I want to leave before it makes me sick again. Not physically sick. I've never been ill a day in my life. Mom, you know that. Your only fooling yourself when you say otherwise. Despite what you say, my sickness is emotional. My sickness can even be described as mental. But it's not physical. Yes, I've spent weeks in bed, but it's because I don't want to get out of bed, not because I can't. Anyway, I've managed to get into the radio feeds and the ship Jayne is on, Serenity, will be touching down in New Melbourne later today. I know it's going to be on the other side of this rock, but I'm hopping a train, probably as you listen to this, and I can get down there before they leave. I don't have any money, but I can do whatever work the captain is willing to throw my way. Plus, I'm bringing food. That's why the cupboards are bare. Sorry about that. I'll send money as I make it, to help some. They probably live on chemically processed, molded protein on the ship, so I'm sure they'd appreciate it. " She listened to the recording again, to make sure she said what she needed to say, then grabbed her pack, and snuck out for the train station.

She was at the docks. She didn't completely know how she got there, but she knew what she was looking for. Serenity wasn't difficult to find. Fireflies aren't exactly discreet. Her brother, a large, ape-like man, was loading cargo into the ships bay. "Jayne!" She yelled to him. He looked around.

"Mattie!" He pulled her into a crushing hug. "What are you doing this side of the rock?"

"Well, I'm better now, and I want off this gorram rock before it makes me sick again. I heard you guys were down here, I thought I could join you."

"I'd have to talk to the captain. How, uh, did you know we were here?"

"That doesn't matter. So where is this captain of yours?" She asked.

"Right here. I'm captain Reynolds," he introduced himself as he headed out of the bay.

"This here's my kid sister, Mal," Jayne introduced her.

"Hi, I'm Mat," she said, taking the hand he offered her.

"Mat? Nice to meet you. Did you're parents name you guys backwards?"

"Haha. Mattie here got's a girl's name," Jayne said.

"Really? What is it?" Mal asked.

"It's Mat," she said.

"Anyway. Mattie here wants to come along with us. You know, get off this rock, see the world," Jayne explained to him.

"I don't have any money, but you can have this." Mattie handed him the bag of food. "Plus, I can do any work you throw my way to earn my keep. I ain't looking to be paid. I'm pretty crafty."

He looked in the bag. "How old are you?"

"Age is but a number."

"She's 17, Mal," Jayne offered.

"Shouldn't you be in school or something?" Mal asked.

"I'm well finished school."

"Does your mother know you're leaving?"

"Yes. She's fine with me leaving. She wants me to be happy, and knows I'd rather be in the sky. Besides, area I'm from ain't too healthy, and she is more than happy to let me get away from it. So, what do ya say, Cap'n Reynolds?"

He looked real long from Mattie to Jayne. Finally, he spoke. "I guess so."

"Thank you captain. You won't regret it. Would you hurt me if I hugged you right now?"

"Now I'm not one for hurting folk, but I'd rather you didn't...Oh there that is." She grabbed him around the ribcage in a hug. He patted her awkwardly on the head. "Jayne, show her to a bunk."

She followed him through the ship. He opened the sliding door to a bunk in the passenger dorm and let her in. He closed the door behind himself. "So, what's going on, Mattie?"

"What do you mean?" She knew exactly what he meant.

"Why are you running away from home? I know mom ain't given you permission to leave. And that accent you're talking with. That ain't yours. Why ain't you in school? And why do you have this?" He pulled a revolver from her belt. She had taken it from her father's gun cabinet when she left.

"I'm not running away...from home. As for mom, she's better off, and safer, without me around. My accent? You didn't used to have an accent either, if I recall correctly. Ain't is a learned term. Once you learn to say ain't, the rest comes naturally. I took father's gun because I need to protect myself."

"From what, Mattie? Who out there could possibly want to hurt you? And you didn't answer my other question yet. Why ain't you in school?"

"School's what I'm protecting myself from. I don't know if mom told you, but that government academy wanted me. They offered to pay for it completely, and told mom it would help me to become better than New Melbourne. She always wanted me to be better than this place. She was sold. She pulled me out of regular school and got me all ready to go to the Academy. A week before I was supposed to start, I had to go for an orientation. They showed me around. Jayne, what they did to these people was horrible. None of them had any life in their eyes! They turned these people into robots. I don't want to be a robot!" She was sobbing freely and didn't realize it until he reached over to wipe tears off her face. "I don't think they knew I knew what was going on. I stayed calm and went back home. Time came for me to go, and I couldn't. I told the man who had come for me I wouldn't go, and he got angry. He said I had to, since I had seen inside already. He said he'd be back for me, and he would make me regret it if I told him no again."

Jayne hugged her. "No government has got any right to mess around in your head. We've got a girl on board, her brother broke her out of the Academy. I don't want you to become that. You made the right choice."

"No I didn't. Jayne, he came back, and I had my bags all packed. I went with him, and I didn't look back. I went to the Academy for a year. I made the wrong decision Jayne. I messed up." She was sobbing uncontrollably. She hadn't said a word about the Academy to anyone before. She couldn't. New Melbourne wasn't the reason she was sick.

"Mattie. Calm down. It's okay now. They ain't gonna get you back. I won't let them. Just, what did they do to you?"

That was it. That's what set her off. She pushed him away, threw her pack at him, then ran out into the corridor. She ran blindly to the bay, were she dropped to the ground and hugged her knees.

Mal looked at her with eyebrows raised as Jayne came running up behind her. "Now this ship's packed right full of crazy, ain't it?" He turned to Jayne and she used the opportunity to run away. "Time to go. We'll discuss the whole crazy sister thing later. For now, find her, and make sure she doesn't destroy anything."

She ran into a girl on the stairs. She intended to ignore it and keep running, but got tripped up and fell. "You're okay." She didn't ask, she told.

She got to her feet and looked at the person she tripped over. Her blue eyes grew wide as she recognized the others already wide brown ones. "You're River Tam. I know you!"

"I'm known by most, now."

"No, I mean, from school." She said the last word like a jinx.

"Yes. I know you, too. You're Matilda Cobb, but no one's called you Matilda a day in you're life." Mattie was surprised at River's state. She took it as a beacon, telling her she had gotten out in time.

"Mattie. Why don't you go get settled into your bunk?" Jayne said.

She stalked off without another word.

The crew was used to her. But she still made Mal jump. She made herself a mystery. She hid in the shadows. She just sit and wait in the shadows. She never jumped out and said boo, but she made his skin crawl nonetheless. She wasn't bad. Or creepy, in general. In fact, the rest of the crew talked and laughed with her like she was perfectly normal. Mal had brought up her slinking around the ship to Wash and Zoe one day, and they both swore they had never seen her away from the passenger dorm or dining area. After that talk, he stopped seeing her in the shadows as often as he had. Today, she wasn't in the shadows at all as he made his way down to the dining area. It was dinner time and for the first time in a long time, since the food Mattie had brought with her ran out, a pleasant smell was drifting towards him. He entered the dining area to find Mattie serving everyone dinner. He took a bowl, and was amazed at first bite.

"Is this the same stuff we eat every night?" Mal asked.

Mattie nodded. "You ain't never had me cooking before, though. If I can make halibut and tuna taste good every night, then molded protein ain't a challenge."

"If you can make this this good every meal, then I think you just found yourself a job."

"You want me to cook? Well, thanks cap'n."

"In other news, Wash, when will we being touching down?" Mal asked.

"Should be breaking atmo in 3 hours, Mal."

"Alright. We touch down, Me, Zoe, and Jayne will go to the rendezvous. Kaylee, you and Mat can go into the marketplace. Get some real food. Wash, you know the drill. Alliance has a base here, so Simon, you and River best be staying on the ship. Chances are, they won't be on this side of the planet, but those aren't chances I want to take."

"How about some strawberries?" Kaylee suggested. She and Mattie were wandering through a farmer's market, getting food to restock Serenity.

"No. Too expensive. Plus they don't last long enough. They'd rot away within a week. I think we should get some potatoes, tomatoes, cabbage. Apples, maybe bananas. Oranges or other citrus fruit would be good, too. Citrus makes people happy, you know. I think we could do with some of that on the ship. We need spices, too. Rice and beans, last forever and I can work magic on them. Maybe some of that cheese stuffs. You know what I'm talking about, the orange powder in the packs? Did the captain give you enough for us to get all that?"

Kaylee checked her pockets. "Yes he did. So, you're really Jayne's sister? What was it like, growing up with him?"

"I'm not big on talking 'bout the past."

"No day but today. Got it. So why did you leave home, decide to join us on Serenity?"

"Don't matter. It's in the past."

"You don't talk much, do you?"

"I talk plenty, I just don't like talking 'bout my past. What the ta ma de is going on here?" People all around the market get sneaking glances at Mattie, and some were just plain staring. "Hurry up and grab that stuff and lets pay. This place gives me the creeps."

They were heading back to the ship with their produce, when Mattie noticed a bulletin board. "Qing wa koa de lie mang." She was wanted. Apparently, someone from the Academy had gone looking for her. The bulletin marked her as dangerous, and warned civilians not to approach her. She tried to get away from the bulletin before Kaylee could read it, but Kaylee was backing away from her. "Kaylee. Kaylee, listen to me. This isn't what it looks like. Just let's get back to the ship and I'll explain everything to you."

They ran into Mal, Jayne, and Zoe on the way back to the ship. "Captain. She's a fugitive. There's bulletins up about her in town," Kaylee sadi.

"Well isn't that something? We've already got a crazy fugitive. Should just leave you here, fight it out on your own. But I'm a kind and generous man, so I guess you best be gettin' on that ship so we can get out of here."

"Too late," said Zoe, as four Alliance officers surrounded them.

"Matilda Cobb, you are bond by law to stand down."

She put her hands in the air. "I can deal with this. I'd hate for you guys to get your hands dirty. I'll meet you on the ship in 5."

Mal crossed his arms and leaned back against the ship. "Don't let me keep you. By all means, go on. Deal with your issue."

She turned to face the officers, her hands still in the air. Her face was dead set and cold. "Y'all might want to step back a few paces," she said over her shoulder.

One of the officers grabbed her wrist and tried to turn her around, to get handcuffs on her, but she twisted his arm around and used him to level herself as she kicked up and knocked guns out of two of the officer's hands. She twisted around and landed a kick on the side of a head, knocking one unconscious. Grabbing another one's head, she threw him, knocking him and another one to the ground. He got up, reoriented himself, and aimed a gun at her. "Stand down," he ordered.

"Yeah, 'cause that worked so well last time." She seized his gun hand and twisted, so the barrel pointed away from her, then she struck at him with everything she had. Knees, elbows, hands, hitting him in the groin and stomach, trying to get him to the ground and his gun away from him. Once she did, she didn't fire at him. Instead, she turned the gun around and hit him, hard, in the face. His head lolled to the side, blood running from it. She had two of the officers down. One turned tail to run, and the other grabbed a gun off the ground and aimed at her.

She threw the gun she took off the other officer at him, and he dropped his own gun. "Not the brightest, are ya?" She said, pulling her own gun out of her belt and shooting the one that was running off, square in the back of the head. "So, what are you gonna do now?" She asked the remaining officer.

In response, he aimed his gun at her. "Good luck shooting me with the safety on." He checked his gun. She hit him in the head with her own and grabbed his gun. She fired into the dirt. "My bad, safety was off." She turned and ran onto the ship. Mal, Jayne, Zoe, and Kaylee followed her on.

"You wanna tell me why four Allied officers just tried to arrest you, and where you learned to fight like that?" Mal said, stepping towards her.

"You wanna get this bird in the sky, before I'm forced to leave more bodies in our wake?"

"Are you threatening me?"

"Not at all captain. It was merely a suggestion."

"And what exactly were you suggesting?"

"Simply that if we don't get off this rutting planet, more Alliance is gonna come after me, which means I'm gonna have to leave more bodies, which I might add, I don't much care to do."

Mal cut her off. "Could've fooled me."

She continued. "Which isn't gonna look to good for you."

Mal went over and pushed the button to close the airlock, then got on the 'com to Wash. "Wash, get us in the air. Matilda here's made some new friends, and I reckon they want us off the planet."

"Matilda?" Wash laughed over the 'com. "Yeah, I'll have us up...Now." The ship gave a jolt and the engines hum grew louder.

Mal turned to Mattie. "You've got some explaining to do."