An AU where Jack was captured by MECH and experimented on.
~~~

"Jack!" Arcee cried. The two-wheeler was livid. They had found the MECH base and had taken care of the soldiers. There were many rooms in the warehouse, and Jack could be in any of them, or in none of them.

"Jack!" Arcee shouted again. There was no answer, and Arcee feared the worst.

"We will split up to cover more ground," Optimus Prime commanded, and Arcee didn't need to be told twice as she ran down a hall. Bee and Bulkhead exchanged a worried glance before going down different halls.

Arcee forcefully opened every door she passed, as most of them were locked. One in particular was fortified, and she charged a shot before blasting a hole through it and stepping through to check. She froze when she walked into what looked like a surgical setup. Her spark twisted when she saw a few bloody items a few feet away from her inside a sink. She stepped forward, afraid of what she would see next, and hesitantly pulled back a curtain. Her spark stopped pulsing for a few seconds as her human partner lay on an operating table, looking sickly pale. His eyes were closed. Looking at his chest, she desperately hoped it was rising and falling, but was still.

"Jack?" she whispered, hesitantly walking over and kneeling next to the table, setting a finger against his neck for any sign of life.

He was cold.

"No," she whispered, looking at his face. There was no emotion. He didn't look pained or distressed. He looked peaceful, and that bothered Arcee even more.

"No," she repeated. "No. No, no, no!" She repeated the word until she was screaming it.

"Jack!" she cried, but knew it was hopeless. Jack was gone.

Footsteps quickly approached, and they were heavy. She knew it was her teammates, they probably had heard her. Bulkhead rammed into what remained of the door and it went down with a loud heavy thud.

"Arcee-" Optimus started as he ran in, though freezing immediately when he caught sight of the teenage boy. Bumblebee whirred in horror as he saw the bloody equipment.

"He's gone," Arcee whispered. Bee walked over to her. This was the third time now he'd see the aftermath of her dealing with the loss of a partner. He couldn't imagine what that was like. He set a servo on her shoulder plate, and Arcee let out a soft wail of agony.

"I couldn't save him. I couldn't save my partner," she whispered, finally looking away from Jack. Bee warbled sadly and pulled her into a side hug. She accepted the comfort this time, and her frame started to shake with silent sobs.

Bulkhead looked around, and found a room adjacent to the room they were in. He raised an optic ridge and bust it open. It was dimly lit, but he could make out an object resting on another table with wires attached to it.

"What in.." he trailed off as he realized the object looked like a large metal body.

"Break-" he cut himself off as he saw another body next to his late enemy. How did they get Breakdown back? He quickly realized the wires weren't attached to him, but to a similar-sized frame. It was less bulky, but it had the same height. The other 'bot was unfamiliar. From what he could tell, it had a blue-gray color scheme. Doing a small scan, his optics widened when he realized it was alive.

"Optimus!" He called urgently. The said bot walked in seconds later, blinking in surprise at Breakdown but then noticing the new 'bot.

"Should we...take him back with us?"

"With caution," Optimus replied. He gently pressed a digit to his audio receptor. "Ratchet, prepare sickbay and...a human berth, and send a bridge to my current coordinates."

Ratchet feared what had happened but only replied and did as requested. Miko and Raf exchanged worried looks. Was Jack alright?

They looked to the swirling green portal expectantly. Miko was gripping the rail so hard her knuckles were white. Bulkhead walked through first, a bot over his back. He didn't look familiar and even Ratchet was confused.

"We found him...next to Breakdown. He's alive, and maybe he can give us answers."

Ratchet nodded and helped getting him situated on a berth and getting him stabilized. He was interrupted by a whoosh sound of the GroundBridge, and everyone was surprised to see Bee half carrying Arcee into the base. He had an arm around her to support her, and she walked as if underwater. That really freaked the kids and Ratchet out. If Arcee was a mess, how was Jack?

They looked toward the bridge in worry. Optimus silently walked through, delicately holding something in his servos. Miko could recognize that hair anywhere.

"Jack!" she exclaimed. If she leaned any farther she would fall over the railing. Optimus had a look of sorrow in his optics as he looked at the humans, walking up to the gurney that had been set up next to them and gently placing Jack on it. The kids stopped in their tracks when they saw him.

"Jack?" Raf whispered, hesitating for a couple of seconds before walking to his bedside. He slowly reached out and set a hand on his. His reaction was slow, but tears welled up in his eyes and quickly poured down his cheeks. Miko took Jack's other hand and squeezed it. She didn't care it was cold. She couldn't believe it.

"Jack, come on, wake up. Please," she whispered, looking at him and wanting to see a smile form on his face and his blue eyes to open. She couldn't feel a pulse.

This was real.

"Jack-" she couldn't continue, bursting into sobs and gripping his cold hand tightly. The bots exchanged glances, save for Arcee, who was still staring at the floor. How would they tell June?

***

June took it much worse than Arcee had. She had lost her only son. She was depressed and angry. She knew she shouldn't be angry at the bots, but she felt as if part of it was their fault. She threatened to take the kids again, but they both refused to leave their guardians and, as of now, emotional support. The Autobots were their family, and June managed to see that. But the kids also were too young for this. They were constantly in danger.

She looked over at the other 'bot they had taken with Jack. She wondered if Jack had seen him, before she covered her mouth to try and choke back a sob and looked over at him. Her son was gone.

She held his hand close to her chest. What she wouldn't give to have Jack back.

The Autobots, though sad for Jack (Arcee mentioned something about revenge again before Optimus pulled her aside), still wanted answers from this other 'bot. He had been unconscious for hours. He had no insignia, so they had no idea if he was a Decepticon or not. When the 'bot was finally coming to, the Autobots took some comfort in fact his optics were blue. Suddenly he realized he wasn't alone and moved away in fear, ending up falling off the side of the berth until he noticed his surroundings and visibly relaxed. He froze again when he saw how much smaller Ratchet and Arcee were. He tried to speak, but couldn't get any words out. Noticing his weird position, he moved to get up, and froze.

What happened to his hand?

He shook his head in denial as he looked and felt the rest of himself. Metal. All metal.

"Are you alright?" Optimus asked, furrowing an optic ridge. His helm snapped up at the sound of his voice and he shook his helm. Did he look alright?

The Autobots were even more confused now. According to Ratchet's scans, he should have been fine enough. Optimus cautiously extended a servo to help the poor bot up, and the 'bot hesitated, before making a decision and taking it. He was about half of Optimus' height, like Bulkhead and Ratchet, though was a bit wobbly on his feet-his pedes.

"Can you speak?" Arcee asked, though roughly. She wasn't in the mood to be friendly right now. The humans had been watching in curiosity since the 'bot had fallen off the berth.

"I..." the 'bot started, managing a word.

"Question answered," Arcee replied.

"What is your designation?" Optimus asked, letting go of his servo. The 'bot looked around uneasily, catching sight of the humans and stiffening when he saw Jack laying there.

"You're...not going to believe me," he said after a few seconds, turning back to Optimus. "But...I'm Jack."

"What kind of joke are you trying to pull?" Arcee hissed. "That's impossible."

"I wish it were," the 'bot-Jack-muttered in reply.

"A human/Cybertronian transformation is completely-"

"What, unheard of?" Jack snapped, looking back over at Ratchet. He even sounded the same.

"Of course it is, because we're two different species and we're not exactly 'compatible'," he continued.

"If you're Jack...then...you would know how you met the Autobots," June interjected.

"I was admiring Arcee's vehicle mode when 'cons showed up and I was dragged along, meeting Raf in the process. The next day, Miko had seen me and Arcee the day after and the three of us saw the base for the first time."

"I believe it," Miko replied seriously, looking at Jack. The Cybertronian Jack.

Jack looked back over at her before shuddering.

"Can someone please get me out of here? It's freaking me out," he asked, turning away again. The others complied, moving the gurney to a room in the base.

Over time, the others managed to get used to Jack being around the base all the time, even Arcee. He was given a vehicle mode; a large pickup truck. Optimus and Arcee trained him to fight after persuading June that he would be useful, and they should make the best of what they had since Jack's change was permanent. Jack himself hated being Cybertronian at first, but grew to tolerate it after a while. He had let Ratchet work with and on his systems to improve them and see how MECH successfully achieved such a freak of nature. Jack took Miko and Raf driving once in a while. Optimus and Jack went on a couple of missions together, and Arcee and Jack went on some, too. Jack didn't want to be called anything else but his name. He wasn't ready to give that up yet. It wasn't perfect, he still missed being human, but he supposed being alive was alright. Maybe this was how it was supposed to be.

~~~
So, that happened.

Smokescreen doesn't exist in this AU, btw, and this is set after the episode in S2 where Breakdown died, obviously.

There will be a part two btw