All the usual disclaimers. Not mine, just playing nicely with the toys.

“Zoe, lamby, what’s the matter? Zoe, ZOE!”

“Simon, get up here!” Wash’s voice rose to a shout over the intercom.

Simon came at a run, followed by Mal.

“What is it, Wash?” Simon asked.

“I don’t know! Look at her -- she can’t breathe. She’s wheezing and sweating, and I don’t think she can hear me.”

Zoe lay in the bunk she shared with Wash, eyes closed, hair sweat-drenched. Her breath came in quick pants and she grunted with every exhalation

“How long’s she been like this?” Simon asked calmly.

“I don’t know. She was like this when I came back down from the bridge. I was up there maybe three, four hours; she was sleeping when I left, just coughing some. She was fine when we went to bed last night, maybe a little bit of a cough. She figured it was haydust and she’d be all right once it settled.” Wash was clearly terrified but holding hard onto his composure.

“What d’you think it is, doc? Do you reckon it’s contagious?” Mal asked.

“I can’t tell anything until I get her up to the infirmary. I don’t like the sound of her chest but I can’t really tell anything until I run some tests.” Simon’s mouth was set hard and it was clear he was a little uneasy.

Mal picked Zoe up from the bed and clambered up the companionway. Wash was right behind him, noticing in spite of his fear for Zoe that Mal hadn’t even asked whether he should carry Zoe. And also noticing that he would have asked Mal to carry her if he hadn’t simply scooped her up.

As soon as Mal laid Zoe on the medbed Simon moved smoothly into action. He fitted an oxygen mask first and as soon as it began to feed Zoe’s breathing grew noticeably less labored. He draw blood and started analyzing it, stopping often to listen to Zoe’s chest, his face impassive. He swabbed inside her cheek and examined the sample under the microscope.

After nearly an hour he turned to Mal and Wash, who both stood over the medbed. Wash holding Zoe’s hand. Kaylee peered in from the door.

“I can’t tell what it is. It sounds like pneumonia but I don’t see anything like a normal pneumonia microbe. I’m going to need to take a biopsy. I’m sorry – it’s going to hurt.” Simon looked from Wash to Mal, as though unsure whom to ask permission of.

“Go ahead,” Wash said. “We need to know what this is.”

Mal nodded.

“You’re going to need to hold her. She’s unconscious now and I’m afraid to give her a sedative, but the needle may wake her. Just be ready.”

“How should we do this?” Mal asked.

“The best thing would be if one of you could sit down and hold her arms against her sides. That way I have a clear field. She’s less likely to dislodge the needle if you’re holding her than if I put her in restraints and she wakes up suddenly.” Simon answered as he prepared a biopsy needle. Mal averted his eyes from the large hollow needle.

“You do it.” Wash didn’t ask Mal whether he would or could, just assumed that if he asked, Mal would do anything necessary.

Mal nodded silently in reply before collecting Zoe’s limp body into his lap and sitting carefully in the infirmary’s sturdiest chair. Simon stood in front of him, opening Zoe’s nightshirt and sponging her chest with alcohol.

“Ready?” Simon asked.

“As ready as I’m gonna get,” answered Mal.

Zoe moaned when the needle plunged in, moaned and opened her eyes. Seeing Mal’s face next to hers she relaxed slightly, whimpering quietly under her breath.

“Easy, meimei, easy, darlin’.” Mal crooned softly, while Wash reached over Mal’s shoulders and stroked Zoe’s shoulders gently. Her eyes fluttered closed and she slid back into unconsciousness.

Simon withdrew the needle and expelled the sample onto a microscope slide.

“Go ahead and make her comfortable on the bed. Until I get the results of this I can’t start anything except the oxygen,” Simon said as he turned toward the medical equipment on the counter.

Wash picked up Zoe’s legs from Mal’s lap and between them they returned her to the bed. Wash refitted the oxygen mask and closed her nightshirt. He tucked the blanket in around her and sat holding her hand, his head on the bed next to hers.

Mal watched Wash settle her, keeping his hands forcibly in his pockets. Zoe wasn’t shot, she was sick, and it was right that Wash should take over. Mal, in spite of his near-constant irritation with Simon, believed Dr. Tam was a phenomenally gifted doctor. He only hoped that the shopping trip Kaylee and Simon had taken on Persephone had netted whatever they were going to need to pull Zoe through this thing.

“Sir,” Mal’s head whipped around to the door. “You said to come up to the infirmary and see the doctor about my cough. It’s kinda worse …”

“Right now we got bigger problems than your cough. Go on up to your bunk. I’ll send Simon to you when he’s got a minute.” Mal glared at the boy until he sloped off towards the dorms.

*** “Mal, I know what it is.” Simon came onto the bridge and sat facing Mal, who had been staring out into the black.

“Well, I know what to do about it, anyway, even if I don’t know exactly what caused it,” Simon amended.

“What is it?”

“It’s a mold. It’s in her lungs, and it’s causing a kind of chemical pneumonia. But what I don’t understand is how she got it. It’s a mold usually associated with mining; tin miners get it. But even then it’s rather rare.” Simon hated not knowing.

“What can you do, doc? Is there something we can do?”

“Now that I know what it is I can treat the symptoms and keep her breathing until her body fights it off.”

“Do you have what you need? Is she going to be able to fight it off?” Mal tried to sound imperturbable, in the best stoic captain tradition.

“Yes. The medicine is pretty straightforward, and she’s young and strong. I don’t foresee any problems that way. But it is going to take a long time. And I’m worried about where she picked it up. She didn’t leave the ship on Persephone, did she?” Simon looked at Mal.

“No. She hasn’t been off the ship since Endymion, and that was more’n a month ago. Could she have picked it up there?” Mal didn’t want to consider what he knew was likely true, that whatever this horror was, it was right there on the boat with them.

“That’s what I was afraid of,” Simon said. “I think we need to assume it’s in something on Serenity. I’m going to test the water and the air. I’ll test the horse’s bedding, maybe it came in with that. I’ll let you know what I find. Zoe’s resting quietly for now,” Simon said, answering Mal’s unspoken question.

“Oh, and Mal, did you say the stablehand was complaining of a cough? I better look at that quickly – he could have it, too.”

“Yeah, he was coughing this morning. I sent him to his bunk – told him you’d stop in to see him.”

“Well, I will, right now.” Simon touched Mal’s shoulder hesistatingly as he left the bridge. He wasn’t given to considering the captain’s inner self, but even he could feel Mal’s carefully masked anxiety over Zoe.

*** “Zoe’s breathing a little easier, Mal. The oxygen’s helping.” Simon returned to the bridge in mid-afternoon, Mal apparently having never moved. Simon knew, however, that he had been down and seen to the horses several times. “Gowan’s looking worse, now, though.”

“And I have the results of the tests on Serenity. It’s in all the water lines and the air scrubbers. The mold is growing filaments and they’re clogging everything. When the water or air passes over it, spores break off and travel. Into everything on board this ship,” Simon reported the news with grim certainty.

“Including Zoe’s lungs,” Mal responded.

“Including Zoe’s lungs,” Simon agreed. “I don’t understand, though, how she got such a large dose when the rest of us are fine. Gowan’s the only other person showing any symptoms at all.”

Mal swiveled around to look closely at Simon.

“Only Zoe and Gowan. Only Zoe and Gowan. This is not an accident,” Mal growled.

“What do you mean, ‘not an accident’?” Simon was puzzled.

“That boy Gowan isn’t the boy we were supposed to take with us. He says he swapped spots with his brother because he needed to get off Persephone. But I’m wondering now if he didn’t need to get onto Serenity. Can he talk to me?”

“Not now. I’ve got him on medicated oxygen,” Simon said.

“Doc, you say this gou se is in the water? If that’s so I think I know why only Zoe got near a lethal dose. It was the shower. She took a long, hot shower while the tanker was filling the water. She was breathing this gou se in the whole time.”

“Yes,” Simon agreed instantly. “If she took a hot shower after this thing got into the system, she was breathing spores in with the steam. No wonder it hit her so hard.”

“So now what?”

“I can treat Zoe and Gowan, and I can watch everyone else for early signs. And we can treat our water so no one else gets a lethal dose until we can get it out of the system. I’ll hand out masks for the airborne spores,” Simon said thoughtfully. “But we need to land, and it needs to be somewhere with a reliable water source and it needs to be soon. We have to clean this ship out before we all get this.”

“And there is the question of our passengers. We need to get those horses out of this boat pretty gorram quick. I contracted to deliver healthy, livin’ horses, not horsemeat. And I don’t fancy puttin’ masks on those animals,” Mal grinned wryly for this first time since Wash had called for Simon that morning.

“So we need somewhere safe with a reliable water source. And we need it quick.”

***End of part 3***