The first time Jack heard the voice, he thought that he'd forgotten about an earpiece. Fargo had them all testing out this new earpiece thing that was supposed to do something more than their old earpieces. Jack couldn't actually remember what their new earpiece was supposed to do; Fargo changed them that often. He was glad that at least this earpiece didn't zap him every time he called Zoe though. However, it did leave him with a mild tingling sensation every time he called Henry, which was a bit annoying since Henry was in Antarctica and he needed to call him often.

Lifting a hand, Jack prodded his left ear but there was nothing there. He frowned. "Hello? Hello?"

Jo raised an eyebrow as she passed him in the hallway. "Talking to yourself?"

Jack hurried to catch up with her. "Did you hear something?" he asked. "Somebody who was whispering my name?" He tilted his head to one side. There it was again! There was a soft insistent whispering of Carter.

"I don't hear anything," Jo said firmly.

Carter!

"There!" Jack insisted as he punctuated the air with a finger. "You have to have heard it. It was loud this time."

Jo shook her head.

Idiot Carter.

"Hey!" Jack exclaimed. "No need to be insulting.

Jo raised an eyebrow. "I never said a thing!" Her tone implied that she was thinking plenty of insulting things though.

Jack shook his head. It had been a long week – full of evil genetically modified flowers. He still had the thorn scratches down his forearms from when the roses decided to revolt. Maybe he just needed a coffee.

The second time Jack heard the voice, he began to realise that something was up. "Who's there?" he demanded. He spun around the room, scanning the corners and behind the couches. There was nobody visible, but that didn't mean much in Eureka. There could have been a whole invisible army in the room.

"Nobody is currently here except you, Sheriff Carter," S.A.R.A.H. told him.

Jack narrowed his eyes. "Show yourself!"

"Who are you talking to?" S.A.R.A.H. asked.

"Shhhh," Jack said softly. "There's somebody else here in this room." He could hear the soft whispering at the back of his mind. It was indistinct; he could barely make out the words.

"There's nobody else here," S.A.R.A.H. repeated.

Carter, you're an idiot every day of the week.

Jack frowned. He could hear the last sentence very clearly. Too clearly. It sounded far too familiar, but no – that was impossible. "Who are you?" S.A.R.A.H. began to respond again, but Jack shushed her. He could hear her making annoyed sounds. Undoubtedly he was going to have to bring her flowers again. Or perhaps buy her the latest season of Oprah – she never admitted that she liked it, but he knew what she watched when nobody else was around.

Who do you think? The voice sounded irritated.

Jack licked his lips; his mouth was suddenly dry. "Stark? Is that you?"

Congratulations.

"Are you trying to tell me that..." Jack couldn't even think of the right words as he waved his hands around his head. It had taken him a while to convince everybody that he was serious. In fact, it had taken Jack writing down some of the key equations of M-theory before people stopped looking at him like he was imagining things. His wrist was sore from all that writing and erasing (mostly erasing, because Stark kept on telling him that he was doing it wrong.)

"Yes, it is possible," Fargo told him helpfully. "It seems that Nathan Stark's back, and you're the only person who can hear him."

Allison looked slightly pale.

"I have a plan," Fargo announced. Jack took a couple of steps backwards as Fargo advanced on him with what seemed like a sharp pointy injection. "We need to be able to talk to him and since you're the only person who can hear..." He trailed off.

"So?" Jack pointed out. "I can tell you what he's saying."

Allison opened her mouth and then hesitated. She reached over and patted Jack on the arm. "You can only hear him some of the time," she said diplomatically. "It'll be easier if we can speak to him directly."

"That's where this comes in handy," Fargo said as he pointed to the syringe he was holding. "This will – hopefully – allow Stark to access your speech centres."

"What?" Jack spluttered. "You want Stark to possess my body?"

"It's necessary," Fargo told him. "I have this machine that will help the process."
He looked far to eager for Jack's comfort.

"Oh no," Jack said. "Stark's not having my body."

I don't want your body, Carter.

"See?" Jack exclaimed. "He doesn't want my body."

Allison took a step closer. "It's perfectly safe," she said softly. Jack couldn't help but notice how she didn't take his hand.

Jack wavered.

It took a good several hours before Jack agreed to sit in Fargo's machine and be injected with the strange purple fluid. The injection stung and as Jack sat still, he felt as though his head was about four times bigger than normal. ("You need to sit still," Allison explained. "That way the formula can diffuse into your bloodstream better." It didn't make sense to Jack, but he sat still anyway.) The other thing Jack noticed was that Stark's voice was suddenly much louder.

I don't like it in here, Stark remarked.

"I get to use my mouth," Jack announced. He ignored the strange looks everybody was giving him.

Doesn't that defeat the purpose of doing this?

"Oh shut up," Jack said wearily. "Fine. Stark, you can use my mouth." He looked over at Allison who was giving him a very odd look.

"Sheriff Carter has been very accommodating," Stark drawled. Jack could feel his vocal cords vibrating, his mouth moving, but it wasn't him saying the words. "I tried talking to all of you, but it seemed that he was the only one who could hear me."

"How long have you been back?" Allison burst out.

"I'm not sure," Stark said. "A while, I believe. The passage of time isn't the same in this dimension."

Allison nodded. "That makes sense. It wouldn't be."

Jack began to tune out. His girlfriend's ex-husband was using his mouth to have a conversation about scientific things that he barely understood. It was a very strange day.

"So," Jack said as he interrupted Stark in what seemed to be an hour-long monologue about strings and probabilities. "When do I get my body back?"

"As soon as I'm finished with it," Stark retorted.

Jack wrinkled his nose. "This is very weird."

"Not nearly as weird as it is for us," Fargo pointed out as he poked at his computer. His face suddenly paled. "Uh oh," he said slowly. He seemed to be mashing his keyboard with his palm. There was a very worried expression on his face.

"What do you mean 'uh oh'?" Jack exclaimed. Or at least his mouth did. Jack wasn't quite sure whether it was him or Stark who had said it. When Fargo didn't answer, Jack repeated his question louder.

"There is a slight problem," Fargo admitted.

"What sort of slight problem?" Jack spluttered.

Fargo's face turned an interesting shade of purple. "The kind of slight problem where I can't separate you two," he said slowly. "I'm sure I can fix the machine. Tomorrow. The day after at the latest!"

Jack turned his head to glare at Allison. "I thought you said it was safe!" The last thing he wanted to do was share his body with Stark for a day or two.

"How do you think I feel?" Stark burst out. "Imagine being stuck in this body."

"Hey!" Jack didn't think his body was that bad a place to be stuck in. After all, he worked out regularly. He was healthy and fit. People said that he was attractive.

"A few days, tops," Fargo promised.

Jack resisted the urge to bang his head against the wall. He could feel similar urges emanating from Stark, except mixed with slightly more homicidal desires that seemed to be directed towards Fargo.

It was going to be a long few days.