"Doctor!" called Zoe. Simon froze and turned around to greet the rapidly approaching first mate.

"Yes?" he asked, as innocently as he could manage.

"The Captain needs you to be working on a few things in the Infirmary," she said, leading him from the cargo bay to his office.

"What needs doing?" he asked, stepping into the room.

"Oh, just to stay put for a few hours," said Zoe. "So do tests, whatever you do to keep busy down here. You aren't gonna open that crate."

"I don't want to open it…I just want to know what's inside."

"Exactly. Get to work, Doctor." She took a seat in the common area pointed directly at the doorway to the Infirmary.

Simon stood awkwardly for a few moments, and then began to tinker around with a few of his instruments. After thirty seconds or so, he abandoned the tools and turned to face Zoe, exasperated.

"Aren't you in the least bit -"

"No."

"Can't we just -"

"No."

Simon sighed, frustrated. "You heard Mal. What's in that box could be dangerous."

"You heard the Captain – it might not be. You also heard him say that no-one goes near it until we reach port."

"But what if it kills us?"

Zoe smirked slightly. "Come on now, Doctor. What are the chances of that?"

Simon threw up his hands and withdrew into the Infirmary, trying to busy himself with menial tasks, but his mind kept wandering to the metallic box stored in the cargo hold. A fierce curiosity was a part of his nature, and he couldn't just flick a switch as the others had evidently done. He had to know what was inside that crate – mostly for peace of mind, so he didn't have to worry about whether it would kill River, Kaylee and the others – but also for the need to just know what was being denied to him.

A glance back to the common area revealed Zoe was quietly discussing something with Inara, and that her attention was partially distracted.

"River," he whispered. His sister, dormant as she was curled up in the corner of the Infirmary, stirred slightly when Simon mentioned her name. She glanced over at him with mildly inquisitive eyes, although she probably already knew what he was going to ask her.

As Zoe and Inara stood conversing, the first mate eyed River as she floated out of the Infirmary, though slightly too engaged in conversation to pay her any heed. She walked past the other two women and headed up the stairs towards the mess. Zoe turned back to Inara fully, now paying the Companion her full attention.

Unobserved, River wandered through the mess and then back down the opposite set of stairs into the cargo bay. She took in her surroundings for a moment, and then scampered down the stairs that led to the far end of the bay: namely the end that held the forbidden cargo container.

She bounded over to the crate, and then hesitated just as she reached the crate. She placed her hands just above its surface, waving them across it. She could feel the waves of coldness emanating from it, giving no clue to its contents. Her hand strayed towards the latch that would release the first seal…

"Hey now, girly," echoed a voice from not far behind her. "Don't wanna be doin' anything stupid now, get me?"

River continued her hand waving activities, passing over the latch in spite of the warning. "Silly. I wasn't going to open it."

Jayne stepped closer to her, gun at the ready – just in case. "C'mon, darlin'. Let's take you on the oddball family reunion." He gently took her arm, as to not provoke a violent reaction, and River allowed herself to be led away from the mysterious cargo container.

Zoe arched an eyebrow upon seeing River, and a glance into the Infirmary showed that Simon was pretending – badly – to be busying himself with some kind of diagnostic.

Jayne firmly planted River in the Infirmary, and Zoe didn't deem it fit to warn Simon to not try anything like it again – Jayne did it for her when he brushed 'accidentally' with Vera a little too close to Simon's leg, sweeping the fabric.

With Zoe returned to the common area and Jayne back in the cargo hold, Simon rushed eagerly to River so she could produce the hidden fruits of her labour – namely, the data from the portable scanner he had woven into the arm of River's sleeve.

"Did I do good?" asked River, vaguely earnest.

"You did great, River," congratulated Simon, and he hugged her gently. She was so strange these past few days; she seemed so…sedated. More than usual, anyway.

Simon loaded the information onto his lab computer and started to read through the data. River wandered over and looked at the numbers scrolling across the screen, as a cat would watch raindrops rolling down a window in a storm. Simon knew that she possessed a greater understanding of the screen than a cat did of how the water arrived at the window, but still…he added it to his growing list of slightly irregular behaviour in his sister. Not that that meant much where River was involved.

He started first of all by looking at the composition of the container, and found that it was a pretty standard compound mix of metal, plastic and other irregularities. What was more interesting was that inside it, there was another, much more sophisticated container that was using the standard one as camouflage. And more interesting yet was that this second, internal container possessed some kind of scanner scrambler, in that according to Simon's admittedly basic instrument, it was empty.

"Curioser and curioser," he muttered.

Why would someone pay to transport a disguised, empty container? Maybe someone was going to fill it at the opposite end of their journey, but that was unlikely, as they had been warned not to open the crate under any circumstances. No, Simon resigned himself to ignorance on getting a concrete reading on the contents; there was something in the crate, but he just couldn't get a scan of it. There were other ways he could get an indication of what might be in there.

The most obvious way was calibrating the weight of the two cargo crates, and then deducting it from the total mass of the package as it was. Considering how heavy it had been to lift, it wasn't difficult for Simon to see that whatever it was weighed quite a bit. Was it a person? Too heavy, and Simon couldn't make a worthy guess of what else might be in there.

Abandoning the weight strategy, Simon moved onto a gaseous analysis of the contents of the box. What he saw amazed him; a gas like none other he had ever seen. So strange it was that he couldn't begin to guess what kind of an effect it would have on a person if it were inhaled. It seemed similar in some ways to an anaesthetic gas, but in others it appeared to be more poisonous than cyanide.

As Simon was busying himself in the Infirmary, another puzzle was forming; however this one had a more immediate solution.

Up on the bridge, Mal picked up a blip on the radar; another ship was slowly gaining on them on an intercept course. He subtly changed their course a couple of times to assess whether or not they were really being followed, however the other vessel quickly proved that it was tailing them.

Unfortunately, it was also bigger and faster than Serenity.

He flipped on the intercom. "We've got company. Zoe, get up here. Jayne, keep an eye on the cargo."

Unbeknownst to Mal, Jayne was making faces and imitating his captain in the hold; "Jayne, keep an eye on the cargo. What the hell have I been doing for the past four gorram hours?"

Zoe marched onto the bridge with a purpose, and Mal filled her in.

"Reavers?" she asked automatically.

"No, they've got containment. Maybe smugglers, but they'd try and keep out of the way."

"Bounty hunters?"

"Maybe," Mal nodded. "I think the good Doctor and his sister would still fetch a decent price on the market. Lil' River probably has some more Alliance secrets up in that big brain of hers they'd rather not get out like the last one."

"Too small to be Alliance," pondered Zoe, and at that moment the communications panel lit up. Mal gave her a look.

"I guess we're about to find out." He flicked the switch that would put through the transmission, and a familiar face showed up on the readout.

"Harvey," said Mal with no small degree of surprise. "Fancy seein' you all the way out here. What can I do you for?"

The Brown Coat's former squad mate didn't look particularly amiable. "Hi Mal. It'd be great if you could reduce speed, let us come on board and, well, I'll be honest, take some of your cargo. The reformed Independents have a certain…vested interest in what you're carrying, and we would like you to donate it to the cause."

Mal considered that for approximately less than a second. "There's more of a snowball's chance in Hell as you setting foot on this bird."

Harvey smiled. "Predictable Mal. But you haven't thought it through, as usual. Shoot first, even if it's with your mouth. I'm in a faster ship, and I have guns mounted on mine. You have neither advantage."

"You want my cargo so bad, you won't fire on me."

"Wrong – I'll knock out your engines, your life support, wait for you all to suffocate and take it anyway."

"That happens, and I open the crate. I assume you know what we're carrying."

Harvey's face almost blanched. "You wouldn't."

"Between that and lettin' you win? I thought you knew me, Harvey." He flipped off the comms, and the screens went dark. He turned to face Zoe.

"Take the helm. Evade as long as you can, and you call me when they get too close."

He rose from his seat and went to leave.

"Where you going, sir?"

"To figure out what's in that crate."

"I can't say how strongly that's a bad idea," said Simon vehemently, and Mal practically had to step back in the face of the force of the Doctor's words.

"Woah, what happened between now and a few hours ago?"

Simon looked away, vaguely sheepish, but it was River who gave him away.

"Take the readings, bring them back. So cold…the butcher told me to wrap up warm."

"I see. Well, maybe not about that last part. But I see."

"I couldn't help it, Mal. It was a threat to us all."

"Well, now it might be the thing that saves us from being blown to itty pieces. What did you find?"

"There were several unusual properties present in the container. Essentially, the most conclusive readings I obtained were of the gas present in the inner container…"

"Doctor," Mal interrupted. "Just the basics, if you please."

"Oh – yes, sorry. Best guess, it's some kind of airborne virus being transported by some kind of medium such as frozen meat."

"So it is a weapon."

"I can't say what it is or isn't with any authority. But based on what I know…yes."

"There's one way to find out for sure," said Jayne, and Mal nodded slowly. Simon looked at them with dawning, horrified comprehension.

"No. You can't open it. I forbid it."

Anger flashed through Mal's eyes. "What did you say?"

Simon realised his mistake, but refused to back down. "If you open that crate, we will be dead within hours."

"So we drag it into the airlock, suit up and take a peek," shrugged Jayne.

"An unusually good idea, Jayne," said Mal.

"Not even that would guarantee your safety. I have no idea what that gas is, let alone how it would react to plastics, metals; I don't even know for sure what the inner crate is made of, so it could react harmlessly with the environment, or for all I know it could eat through your visors in seconds."

"In a vacuum?"

Simon looked exasperated. "Yes, Jayne. Being in a vacuum doesn't ensure safety against corrosive elements, it just means when something does hit your suit you suffocate."

"Tell me Doctor, what does a surgeon know about airborne toxins?"

"Enough to know that opening that crate is a very bad idea."

Mal pursed his lips, and then wandered out of the Infirmary. Jayne followed him.

"So are we openin' it?" asked the rough and ready mercenary.

"…No. We'll use that as Plan B."

"So what's Plan A?"

"I'm still workin' on that."

"Well I'd come up with somethin' fast, cause I doubt your guy will stick around until you've thought somethin' up."

"Cap'n, we're being raised again."

Mal ran to the bridge.

There, he met with Harvey's grim face.

"Oh, you again," he greeted. "Don't you have anythin' better to do?"

"Stop it, Mal. I want to make a deal with you, because I don't want to blow you and Zoe up, so I'd work with the situation instead of trying to worm your way out of it."

Mal exchanged a glance with Zoe, who just shrugged. "I'm listening," he said.

"It's simple. You give me that crate, and I let you go unharmed. You know my methods, Mal. You know how far I'll go to get what I want, and you know that my ship is pointing big guns at you right now. The decision's yours."

"Why do you want the crate so much?"

"Why do you think? For what's inside. I doubt they told you what it is, but it could revolutionise our war against the Alliance."

"Y'see, this is why I said no to you. Every time someone's had the bright idea of resurrecting the Independents, they blow up coffee shops, gas children or one of a hundred other ways not to do business. Yes, I killed men in the war, probably some women too. But I did it on the field, and I did it when they had a gun in their hand."

Harvey snorted derisively. "Don't talk to me about sensibilities in war. We all did questionable things, Mal. I'm not going to have this conversation with you, so you can stall by goading me into a righteous fit of anger. Tell me right now, yes or no, do we have an understanding?"

Mal stared for a few seconds, and then nodded stiffly.

"Good. Wise decision. Oh, and Mal? Try anything, and I shoot you."

"Got it. And for the record, I wasn't stalling."

The monitor went dead again, leaving Mal steaming. Zoe cast him a sympathetic eye.

"You did the right thing, Captain."

"No Zoe…I did the only thing, and sometimes they ain't the same."

He stomped off the bridge and made preparations to receive guests.

He ordered everyone except Jayne and Zoe into the passenger dorm and instructed them to shoot anyone coming through before they heard the other ship depart. That done, the trio waited in front of the main airlock which opened shortly after the aggressor ship clunked into place.

The door swung open, and Harvey, accompanied by a gang of little more than thugs, strutted onto Mal's ship.

"Evenin'," said Harvey.

"Just take it and leave," Mal almost spat. Harvey nodded to his subordinates and a group of them carefully hoisted their lone cargo into the air, and then off the ship. Harvey smiled.

"See? That was easy, wasn't it?"

"We got nothin' to say to one another once this is done," said Mal, and it was clear that Zoe felt the same way.

"That's a shame, Mal. After all we've been through. By the way, I'm gonna have to alter our agreement slightly. Don't panic; I'm just gonna hit you with an EMP blast after we leave, just so you don't get any ideas about chasing us down for vengeance. Which I know you'll have in mind, Mal."

"Fine. Like there's anything we can do about it. So that's what you were doing on Taurus? Scoutin' our outfit, lookin' for a weak spot?"

Harvey shook his head. "Nah. True, I was there chasing that crate, but I didn't know it'd be you guys transportin' it. That thing is a hot potato, it's been changing hands for weeks."

"Why? What's in there?"

He chuckled. "I got no idea. It's hot enough that no one wants to be caught handling it, but everyone wants it. By now it's impossible to find out where it came from first, but I know where it was going to end up, so I guess we either sell it to them or use it ourselves. All I got told was it might be a weapon, and not to open it under any circumstances."

"So someone knows what's in it."

"Hell, Mal, I'm sure God knows, but he ain't squeakin'."

"You're tellin' me no-one knows what's in that crate?"

"No-one I know, anyhow."

"Yet you know it's a weapon."

"I don't know, what I got told was that it's probably a weapon. What do I care?"

"Exactly…" said Zoe. "What do you care?"

Harvey shrugged and spread his hands. "What can I say?"

"Goodbye."

He waved at the assembled group opposite him. "Anyone else Mal, and you'd be a floating hunk of scrap. I hope you know how…"

"Get off my ship."

Harvey smirked, turned and withdrew. The cargo door slammed behind him, and moments later the ship clunked again, departing this time. A run to the bridge revealed that it was moving away, and hadn't so much as aimed its weapons at Serenity.

"At least he was true to his word," muttered Zoe, and Mal grimaced, taking little consolation in her words.

"We're gonna have a tough time explainin' this on Beaumonde."

The EMP cannon swivelled suddenly and fired at the smaller ship, the deck rocking slightly beneath their feet. The electronic equipment blinked and died around them, and they were plunged into almost perfect darkness.

Mal sighed. "I'll go get Kaylee. Zoe? Go and find those candles."

Over on Harvey's ship, the captain ordered a course for the nearest home base, and instructed his crew, much in the same way Mal had done, that they should not under any circumstances open the crate that was now stowed in the cargo hold. Some were mildly curious, but Harvey's rule over them was almost as absolute as Mal's, so other than a few minor exceptions, no one cast so much as an inquisitive eye on the crate.

Which, ultimately, was what betrayed them. So invisible had the crate become that no-one heard the minor whirring inside it, nor saw the lights blinking along the side, nor the lip of the crate popping open, until it was too late.

Pale, almost colourless gas emerged from the open container, reaching malevolently towards human lungs that would inhale it.

Six hours later, every person on the ship was as good as dead.

Next on Void

"Uh…gimme a few more hours."

Thanks to Tyramir, billmovementforever and BlueEyedBrigadier for your reviews and feedback. I hope you like it as much as the story progresses :)