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Chapter One-

"Ianto, you and Owen go around back and enter through the back door. Gwen you and Tosh go through the garage, I'll take the front door. If that thing attacks, shot first ask questions later, do not, let it touch you!" Jack ordered, everyone nodded and split up, going their separate ways. Jack through the front door, Owen and Ianto round back, Tosh and Gwen through the garage after Tosh managed to get it open after messing with the device in her hand. Their guns were raised. Tosh and Gwen walked around the car,
"Looks like the someone's in" Tosh noted.
Gwen didn't answer but she didn't need to. She tapped her ear piece,
"Jack" she said. "There's a car in here, someones inside."
"Got it" Jack said, "I'm in. Looks clear down here." He meet Owen and Ianto in the kitchen and they walked up stairs, single file. Gwen and Tosh entered through a door in the side. They scooped out the rest of the down stairs. No one in the dinning room, no one in the games room, the bathroom was clear too. They followed the others upstairs. Keeping their eyes open, not daring to blink for even a second.

They were hunting something Jack called a Fraennian, he said they are poisonous to humans if bare skin comes in contact all the time they're alive, so every team member was wearing gloves. Fraennians have weak legs and they can't talk at all. Once on the top landing they split up again, Owen and the girls going left and Jack and Ianto going right. There were four bedrooms and a bathroom. Gwen looked into the first room. Clear. Tosh the second. Clear. Owen looked into the bathroom. Clear. Ianto the third room.
"I got him!" Ianto shouted. "He's in here!"
The rest of the team came running towards Ianto's voice and joined him in the doorway. The Fraennian wasn't there but the man who lived there was. On the floor, laying there. Owen lowered his gun and ran over. There was no sign of the Fraennian anywhere. They looked over at Owen and the man.
"He's not dead but he is out cold. Come on, help me get him up."
Then suddenly the wardrobe door open and the alien stepped out.
"Owen, look out!"
BANG!BANG!BANG!
The Fraennian fell down dead. They packed the dead body into the first SUV, Gwen and Tosh then drove the SUV back to the hub. Jack, Ianto and Owen followed them in the next SUV with the other man in the back with Owen.

When they got back to the Hub they put the Fraennian and man in the medical bay. Owen said he would do the autopsy later, right now he had to try and get the man to wake up. Ianto went off to make Coffee and Jack was pretending to do paper work and Gwen and Tosh were watching Owen. Jack eventually came down to watch as well and Ianto was handing out coffee and about to head down to the archives when the man woke up. Looking around him and then down at himself and smiling. He looked back up at everyone around him and jumped.
"Welcome back" Owen said, looking at the man strangely. "Can we have your name please."
The man didn't say anything, he reached out for Owen fiercely making Owen jump, but when nothing happened Owen freed himself and looked at the man again.
"Are you okay?"
Again no answer. Owen picked up a device on the table not to far away and he held it up to the man while it buzzed and then Owen cursed and put the thing down.
"This isn't who we think it is" he said. Letting out a sigh and turning back to the man, looking into his eyes with a torch. "I don't know how but that Fraennian of yours, manged to leave his body and put himself in this man's body. The thing you shot back at the house was an innocent man."

...

They sat around in the conferrence room, looking at each other but saying nothing. They just sipped at their coffee's and tried to think of an explanation.
"How did this happen?" Jack asked, standing before them and demanding an explanation. He'd just killed an innocent man and he wanted answers. The man they'd killed was trapped inside an aliens body and he must have been confused and scared and they just shot him and now he wanted to know how it happened.
"I don't know. Maybe if I dissect the dead body, I'll find something, but, you never know" Owen said.
"Do it!" Jack said, Owen got up and left, everyone else remained seated. He took a few deep breaths, trying to decided what to do next. "Ianto, go down to the archives and see if you can find a file on the Fraennians. Tosh see if there have been any reports of UFO sightings, if there's one, theres bound to be more. Gwen, see if you can find anything about the people who live in that house, I want to know who that man is and if he had any family."
Then they all left and Jack fell into his seat. This was going to be a pain the ass. He ran a hand through his hair, what were they going to do now? There was an alien in a human body down in the cells and it couldn't talk. So, they had to think of another form of communication.

Jack went down to the archives, at the moment he was feeling very low of himself but talking to Ianto always made him feel better. He sauntered down into the archives, his feet hitting the floor heavily, his hands in his pockets. He saw Ianto pulling out the file and he cleared his throat to get the young mans attention.
"I have the file for you" Ianto smiled, holding it up so Jack could see it.
Jack smiled back at him and turned, leaning against the wall and letting out a deep breath. Ianto watched him, his face blank but he was concerned for the older man. Jack rarely came down to the archives unless he was going to invite Ianto up into his office. Jack didn't look like he was in the mood for any of that and Ianto was sure the team was still there too. Jack at least had the common decency to send the others home or make sure they were out and would be for a long time.
"Are alright, Jack?" Ianto asked, although he hadn't called Jack sir for a few weeks during work hours (what he said while they were in Jacks bunker was no one else's business.) it still felt weird to say it.
Jack turned his eyes to Ianto and pushed of the wall, walking over to him slowly, his eyes never leaving Ianto's.
"If Owen is right, about the alien and the man then... We killed an innocent man today" Jack told him.

He was clearly really beaten up about this. They had shot innocent people before, never on purpose of course, through confusion and someone getting in the way. More times than not, the person survived. This was one of the times when it just didn't work and it was too late. Jack always felt bad when those things happened. Someone had remind him it wasn't his fault and it usually either Ianto or Gwen, Gwen only did it when Ianto didn't get there first. Ianto smiled at Jack reassuringly,
"There's no way any of us could have known that in time to save him. Lets focus on figuring out what to do next."
Jack took the file from Ianto and slung his arm around his shoulders and they walked back up into the main hub area. Tosh said there had been no sighting recently and Gwen was printing out a file on the man they found. Owen came up a little while later, saying he'd found something in the aliens pocket that he wanted a second opinion on. They all looked at the thing in Owens hand. It was a small circle shaped piece of metal, the same size as a large coin. Jack took it from him, and examined it. It was pure silver, heavy and smooth. There were several other circles on it, he held it flat in his hand and put one of his fingers on outer circle, moving it clockwise.

The next thing everyone knew they were opening eyes that they didn't remember closing and getting up off the floor, moaning and groaning because they all had headaches. Then they all looked at each other and screamed. They had all swapped bodies and now they looked down at themselves.
"Ianto, I'm in your body and not in the way I was yesterday."
"Well, at least we know who Jack is... Looks like I'm... Oh, for god sake, I'm you, Harkness."
"Look's like I'm Tosh"
"I'm Gwen"
"That means I'm Owen then, doesn't it. Terrific."