The lid to the container had slid off. This had happened before, the first time it started shaking, so Carson wasn't entirely too worried. As he went to put it back in place though, his toes sank into a hot gooey puddle. It had outright melted and boiled over the sides of the container! He dropped the lid with a clatter and peered inside. Sure enough, some strange viscous fluid now filled the container completely and continued bubbling up, oozing over the edges to pool around his feet. He was stunned. Was that the end of it? It couldn't handle the conditions on the ship and just broke down completely? Of course, in liquid form, it would be easy enough to scoop up a sample and do some proper testing. Perhaps he should worry about himself first though. Showering it off his feet seemed rather prudent, but how would it react with water... and would it contaminate the ship's hole supply when it passed through the recycling filters?
As he began to step back and consider things further, the container full of liquid suddenly pitched forward, splashing him with a huge wave of thick alien glop that took him to the ground, utterly drenched. He suddenly felt rather numb, and couldn't get his legs back under him to stand. To his horror, he suddenly found even the outline of his legs within the goop was becoming indistinct, as if he was melting away. Reaching in, his hands just sank right through what should have been his knees, before joining them. There was no pain from any of this to distract him from the pure panic of the situation, but it was somehow breaking down his entire body too fast to react in any useful fashion. Most unsettling of all, the last thing he saw before everything went black were his own legs... just sort of extruding themselves from the far end of the spill.
Carson came too again with a scream as the whole process seemed to run in reverse. He was just a head and a set of arms at first as the puddle slowly spat him back out, crawling away even as his body reformed, barely registering the indistinct appearance of a set of legs as they liquified nearby. Blind panic sent him flying from the room in something halfway between a crawl and a stumbling run, realizing that everything felt wrong, but too blinded by fear to register what. It was only after locking the door and collapsing in the nearest chair that it fully sank in. It wasn't his body that had reformed.
The breasts were the most obvious giveaway, making their sudden presence quite well felt as they bounced around freely in his flight, and it didn't take much effort to confirm the rest. He was a woman. Quite a bit shorter and slighter than his usual self at that. Fortunately, the shock at the whole ordeal of melting and reforming left him too mentally numb to really panic further. Instead, he took a clinical approach to the matter, finding a mirror to more properly examine things. Clearly, the woman in the reflection wasn't him. Aside from the obvious, she looked Korean... and like she was barely out of high school. Perfect skin, perfect teeth... somehow a weirdly familiar face. It took a few minutes before he made the connection, and a quick check of the cryo pods confirmed it. Kim's was empty, and somehow he was in her body.
A younger version of her body at that. Kim had honestly been one of the older members on the crew, hair long gone grey, face creased with wrinkles. The face in the mirror though was so youthful it was like the entire aging process had completely reversed. Not maturation obviously, which is really a separate biological process. She was clearly an adult... or he was, he corrected himself. It was still hard to accept the reflection as his own. If he was able to get the body back to her, he was sure she'd appreciate the sudden increase in youth. Hell, Carson hadn't felt this alive and alert in years, but a good chunk of that was likely just adrenaline. But how had he ended up in her body like this?
Carson checked the logs. It had been another three months since he'd originally unthawed. Apparently Kim had been woken up to check on the thing in the cargo hold again, which had undergone another temperature spike. The same thing must have happened to her as it had to him... but why would she check it out alone? She had to have realized something was wrong when she saw his pod was empty... for that matter, a crew member vanishing should have tripped the security routine and woken everyone up. Unless...
Slowly turning to look, Carson saw something deeply unsettling. "Carson" had returned to his pod. Some idealized youthful version of himself at any rate, with a full head of hair, a flatter stomach, and no sign of the scar he'd had across his cheek since he was seven. Naked at that. Both his clothes and Kim's were lying somewhere under the puddle at this point, and he had a lot more to worry about than retrieving them. Mostly the fact that he was staring at some sort of alien doppleganger after spending several months as a puddle of slime.
It was possible they'd be able to get back to normal just by running things in reverse. He could step back into the puddle, giving Kim her body back, and then they could push the imposter in to get Carson restored. That of course was assuming it worked consistently like that. But then, Kim would have no way of knowing what had happened to him. She'd just think the imposter was him, having taken a quick dip in the fountain of youth, probably blast him out the airlock, to drift around as an unconscious blob while an alien returned to earth. He'd rather like to interrogate the thing besides... but not without getting the rest of the crew up to speed first.
Carson gave the temperature readings another glance and saw things had dropped back down to normal levels. Seems he might have missed the window on restoring Kim anyway.