(Disclaimer: I do not own Criminal Minds or it's characters)

I've been building up the courage to write this and I just had to do it.

So this is a de-aged fic, which has become my favourite genre in fanfiction, but there aren't enough! So I've taken it upon myself to add to the pile.

Here's a quick overview: Hotch and JJ have been together for over a year now; Haley is still alive and this is set in around season 3, Gideon is gone and Rossi has been a member of the team for some time now. Now comes the real AU part; JJ caught Will having an affair and they split up. Likewise, Haley and Hotch are divorced due to his work, but also because Hotch had feelings for JJ. Henry and Jack are shared between their parents...I think that's most of the general overview, I'm not going to go into anything else because you will find out soon enough. But just know that Spencer will get de-aged ;)

Okay, that will do for the AN.

Please review and I hope you enjoy!

JJ sighed as Henry turned his back on Aaron and marched from the room. Aaron's smile dropped and he collapsed onto the bed and dropped the ball he'd gotten Henry.

"Hey, it's okay," JJ soothed, sitting beside Hotch and wrapping an arm around him to make him feel better as he rubbed his face with resignation.

"I just wish they'd accept us. Jack's the same with you," he grumbled.

"Just give them time-"

"It's almost been 13 months, Jay."

"I know, I know. They've almost accepted each other. Baby steps as Garcia says," she winked, putting her hand over Hotch's.

"Sure," he grunted bitterly, getting up and leaving the room. JJ followed behind and he stopped at the door, turning to her.

"I'm sorry, I shouldn't be taking this out on you," he mumbled leaning in for a kiss. JJ raised an eyebrow and teased him with her lips, but quickly put a finger between them and smirked.

"I know what will make you feel better."

"Oh really," He asked sensually. JJ rolled her eyes.

"Not that," she snorted. "Better." She hopped down the hall and Hotch hurried after, with a bemused grin.

JJ ducked under the sink and pulled out a box from the cabinet. Hotch frowned at the box as he read it.

"Pregnan- Wait..." JJ nodded eagerly as shock registered over his face.

"But I thought...the doctors said...I-I," Hotch babbled breathlessly.

"They said it was pretty unlikely, but I guess our trying might have paid off," She exulted, biting her lip with excitement. "I had a feeling and I'm late," she added. Hotch jumped up and pulled her into his embrace, swaying happily as he kissed her forehead.

"You have to test! We have to be sure!" He insisted, peppering her with kisses as she laughed.

"Okay, bossy! I'll do it now, but not in front of you," she retorted. She pulled out of his arms, pushing him back and shutting the door before he could argue. He waited with a boyish grin plastered on his face. He heard the toilet flush and unable to wait much longer, opened the door.

"Hey! I might have been indecent!" JJ cried.

"I wouldn't have minded."

"You're as bad as Rossi," JJ chuckled as she placed the test on the sink. Hotch stared at it eagerly, waiting for the lines to show and praying two would be present.

"How long?" He asked.

"3 minutes."

They waited.

JJ squeaked when the first line appeared a few minutes later. She waited for the next line to appear. After 5 minutes of waiting nothing changed except for the one line.

"What does that mean?" Hotch scowled, knowing the answer already, as he lifted the box disappointedly.

"One line means...not pregnant," JJ mumbled sadly. Hotch dropped the box and collected her into his arm, trying to hide his disappointment.

"We can try again," he said optimistically. JJ pushed him away and sighed.

"We have been trying." She left Hotch standing alone in the bathroom, looking down guiltily at the test. He knew this was his fault. The doctors had said he was much less fertile than JJ and there was little chance of them having kids. He knew she wouldn't blame him, but he had a niggling voice that kept telling him it was all his fault.

Hotch and JJ got to the office early, exchanging a few words on their way. Hotch smiled when he saw Spencer fiddling with a small plastic pot, setting it down delicately and watching with animated excitement from the edge of his desk. As expected the pot flew into the air and landed on one of the empty desks.

Spencer grinned at the distance he'd achieved and stood up to retrieve the pot when he caught JJ and Hotch watching him. He stood up straighter, his cheeks flushing red.

"S-sir...I-I was...uh."

"I know what you were doing, and we've talked about this," Hotch warned, hiding the smile he saved Jack and Henry.

"Y-Yes, sir. S-sorry sir," stammered the young man, collecting his pot and shoving it along with the other parts in his draw. JJ shook her head and planted a kiss on Hotch's face before he departed to his office and she trotted to hers. They felt a little bad for leaving Spencer in the bullpen alone, but he was 26, they had to stop treating him like a child sometime.

It was a few hours until JJ came out of her office with a stack of files and waved her team into the conference room. She stuck her head in Hotch's office and he nodded, setting down the report he'd been filling out. She tapped Rossi's door and hurried to the conference room where Garcia was already waiting.

"This one's weird, JJ. And I'm not talking typical weird, I'm talking about a weird that hangs from the ceiling and drinks blood," JJ frowned at her choice of words. "I'm not even sure if Boy Wonder can wrap his head around this one," Spencer walked in and scowled thoughtfully.

"Huh?"

"Read the file and you'll understand."

They all sat around the table and opened their files while Garcia and JJ stood up to present the case.

"Grab your go bags crime fighters, this one is in Franklin, Ohio and...it's a strange one."

Spencer looked up from reading the entire file, his brow furrowed curiously.

"4 people have gone missing in the Franklin area," JJ clicked a button and 1 young man, 2 older women, and an even older man filled the screen.

"Lana Madison was taken 2 weeks ago. Thomas Fallon one week ago. Nick Davon 3 days ago and Lydia Marsh this morning."

"Any bodies?" Emily asked, looking up from her file.

"Yes...a-and no," Garcia said, waiting for JJ to click the remote. A picture of a teenage girl around 14 years old came on the screen, her eyes were open and blood dripped from the hole in her head.

"Who's that?" Questioned Rossi.

"According to DNA that is Lana Madison." The team gaped at Garcia in disbelief.

"She looks at least 30 in the other photo," Morgan pointed out.

"She was coming to her 33rd birthday," nodded Garcia.

"But that victim can be no more than 15."

"I know! I told you this was weird," Garcia exclaimed.

"It's gets worse," JJ added. The picture of Nick came back on screen and the team saw the whisks of gray in his brown hair. JJ pulled up the image of the next victim who looked around Spencer's age, however, Spencer looked exceedingly young for his age.

"Again DNA came back and they found it was Nick Davon's body. He was 57 years old," Garcia added.

"I don't understand... those dead victims can't be the same people," Spencer mused, his brain whirring as he tried to come up with an explanation.

"I'm afraid they are. The police found Thomas's body as well, he was 28 when he was taken," a picture of a young boy, 10 or younger came on the screen and Hotch had to turn away. The image reminded him too much of his own son.

"I-its scientifically impossible!" Argued Spencer, shaking his head at the file.

"It looks like it is possible, Pretty Boy. This guy must be a scientist of some kind. He's experimenting whatever...this is and testing it out on different people," Morgan began to profile ignoring the shock in the room.

"Impossible", Spencer mumbled as the team started to throw ideas back and forth.

"He's trying to improve his experiment. It looks like he's trying to...I don't know how to explain it, but reverse the aging process," Rossi added.

"He's becoming disorganised. Victim one was kept for a whole week before our Unsub killed her and moved on, the others have been kept and killed in quick succession, which means Lydia doesn't have much longer," the others nodded at Hotch, except Spencer who was still staring disbelievingly at the file.

"Wheels up in 10. Get your go bags."

They got to the station to find a room had already been set up for them and there was information covering a board.

They sat down with the Sheriff and some of his officers and discussed the case. The sheriff listened quietly as Reid went off on a tangent.

"So we're looking at some kind of experimental scientist?" The sheriff asked and Reid nodded, but Hotch cut him off before he could go off into another fit of rambling.

"He has made discoveries beyond any other scientist, therefore he is incredibly smart and highly dangerous. He is also from this area, It's his comfort zone."

"We have Dr. Eton down as a suspect, does he fit your profile?" the deputy queried.

"We prefer to construct the profile before we look at the suspects," Hotch said. The door opened and a young woman stepped inside.

"Sir, the doctor you contacted is here," a young officer hung from the door handle, smiling broadly at the agents.

"What doctor?" Hotch frowned.

"Well, our suspect worked with this guy and we called him in to see what he could tell us, but if you want we can have him wait until you have constructed the profile," the Sheriff explained and Hotch sighed.

"Reid and I can go talk to him, Hotch," Morgan offered.

"Fine, but Dr. Eton is not the unsub yet."

Morgan dragged Reid from the chair that he'd slowly been getting used to and down the hall to where the young officer was stood speaking to a greasy looking man. The man looked up upon hearing Morgan and Reid's footsteps and gave them a smile, his face creasing with wrinkles.

"Hello, I'm Dr. Jarvis," the older man said, extending a hand to Morgan who took it, but Reid chose to wave instead.

"I'm Agent Morgan, this is Dr. Reid. We were told you had some information on Dr. Eton?" the Doctor nodded enthusiastically. He looked at Reid and smiled again

"Yes, I worked with him; He's an excellent scientist. He was making new discoveries almost every day."

"Were these 'discoveries' dangerous?" Reid asked. The doctor paused and looked thoughtful.

"I wouldn't know, he was a very private man in that sense. All I know is that I couldn't compete with him anymore which is why I left."

"Did he ever talk about...uh...attempting to reverse the aging process?" Morgan asked awkwardly. The doctor frowned and then the corners of his mouth turned up.

"Agent, I said he made some discoveries, that on the other hand is groundbreaking science. But as I said he was always very secretive so I never knew what he was doing, so it is possible he was conducting his own experiments- what's this about anyway?" he asked, peering up at Morgan his eyes flicking to Reid curiously.

"He's under investigation. We can't enclose any details at this time."

"Oh, I see. He hasn't done anything wrong has he?"

"We will soon find out. Thank you for your time," Morgan extended his arm again and the doctor took it, but his eyes were on the younger agent.

"That's no problem, agents."

"Weirdo or what?" chuckled Morgan when the doctor was out of earshot. Spencer gave him a nudge, fearing the doctor could hear them.

"Did you not see the guy, Reid? Looks like he spends his life working and not keeping clean."

They walked back into the conference room and Morgan shrugged.

"He said that Eton made 'discoveries' and that he was private, but that's it."

"Okay, let's get working," Rossi said, rubbing his hands together eagerly.

"Reid, JJ, you two stay here and work with Garcia to see what you can find on Eton. Emily, you and I are going to speak to the victim's families. Rossi, you and Morgan head to the crime scene," with that they all dispersed, leaving JJ and Reid alone.

"You know when you have a bad feeling that a case isn't going to end well?" muttered Reid. JJ looked up from her file and frowned.

"How so?"

"I don't know. It's just...I can't explain it."

"Maybe you should take a break from this. Grab some food or something, I'll cover for you," JJ offered. Reid stared down at his coffee dregs and sighed.

"I could do with some coffee," he agreed, standing up to leave. "You want some?" Spencer took JJ's grin as a yes.

"Where's Reid?" Rossi asked noticing the absence of their youngest member.

"He went to get some real coffee...actually, he should have been back by now," mumbled JJ.

"When did he leave?"

"Like an hour ago. I thought he'd go to the one across the street."

"Try his phone," Hotch ordered, his brow furrowing. Morgan pulled his phone out and rung Reid. The phone went to voicemail after 4 rings. Morgan looked up and shook his head.

"You know the kid, he's easily distracted. I say we give him another half an hour before we take drastic action. and by that, I mean having Garcia track him down," Rossi suggested. Hotch and JJ exchanged an uneasy look at the idea of ignoring Spencer's absence, but the likelihood that he was in any danger was low and they had a case to solve.

Half an hour flew by and after they glanced outside for any sign of their youngest member, the team called Garcia.

"Hey, Baby Girl, could you do your boy a favour?"

"Your wish is my command, what do you need my God of chocolate thunder," came the bubbly reply.

"I need you to track Reid's phone."

"Wha'? Why? Where's my Boy Genius got to?" Garcia asked worriedly.

"That's what we'd like to know, so could you track him?" a silence followed as Garcia worked her magic.

"It says that he's at the coffee shop opposite you. It look's like he's round the back-"

"Thanks, Garcia," Morgan left his phone and sprinted across the department, yanking the doors open. He was followed closely by Hotch and JJ.

They ran around the back of the coffee shop and stopped; Reid was nowhere in sight.

Morgan scanned the floor and knelt down to pick up Spencer's phone; its screen was smashed.

"We have a problem."

Spencer opened his eyes groggily and squinted at his surroundings. The room was well-lit and looked like some kind of lab, but it was empty. He realised he was laying down and he tried to sit up, but his arms and legs felt as if they were glued down. He pulled against the restraints as panic gripped him, the cold chill of the metal table he was lay on suddenly became too real.

"Don't struggle agent. There's no point." Spencer's eyes darted around. He panted uncontrollably. An older man walked through a door to the left of Spencer. He was balding and what hair he had was a greasy grey, that hung limply beside his ears. His face was full of wrinkle as if he'd spent his life squinting and scowling.

"Please-" Spencer begged, but the older man shushed him as he came closer.

"Shhh, agent. There's no use in begging. You're my last hope," he muttered, running his hand through Reid's hair as the young agent bucked out against the restraints. Spencer suddenly realised it was Dr. Jarvis who he had talked to several hours before.

"D-Dr. Jarvis? Last hope? What do you mean? Why didn't the others work?" Jarvis ignored Spencer and pulled a tray over to him, Spencer felt his heart rate pick up when he saw a needle sat on the tray. He needed to distract Jarvis to give his team more time. "Did Lydia work? Is she okay?"

"So many questions. You know you shouldn't question adults."

"I am an adult," Spencer retorted bravely.

"Hmm," Jarvis grumbled with a smirk.

"Where's Lydia?"

"She's somewhere around here. She wouldn't have worked anyway. When I saw you I knew you were my last hope. Let's just say you're her replacement," Spencer gulped nervously. Jarvis turned his back and Spencer strained his neck to see what their Unsub was doing. Jarvis prepped the needle, giving it a tap and turning back to Spencer. Reid saw Jarvis armed with a needle and he began to struggle harder.

"Help! HELP!" Spencer screamed. The older man simply grinned down at him. He set the needle down and picked up the duck tape, securing a piece over Spencer's mouth so he couldn't protest

"That's better. I made this batch just for you, please show a bit gratitude," he growled yanking harshly on Spencer's hair and eliciting a grunt from him. He picked up the needle and Spencer felt hot tears fall down his face. I don't want it, he tried to yell, but Jarvis couldn't hear him behind the tape.

He knew the chances of overcoming an addiction a second time was practically impossible.

"This might hurt a little," hissed Jarvis as he lined the needle up to Reid's neck. Spencer shifted to try and avoid the needle, but a large hand clamped his head down. It smacked back into the table and Spencer saw stars for a second before he felt something sharp, unexpected and most definitely unwanted slide into his neck. He froze as Jarvis pushed the plunger down. A warmth spread through his neck and through his body. He felt a tingling sensation burn inside him.

And then came the pain.

Spencer screamed through the tape. It felt as if he was being crushed, his bones popped slightly and Reid thought they were breaking.

Jarvis watched with sick pleasure as the young man writhed and sobbed. He would've watched the whole process but he had things to do and clear up. On his way out he turned the lights out, plunging a terrified Reid into darkness.

"Our Profile is off," Hotch announced, slamming the file down in frustration.

"Then we will just have to fix it, Aaron. We can't give up," JJ soothed, rubbing a soft hand down her partners back.

"JJ, Spencer has been missing for a day now! Lydia is still out there and our profile is off!" He snapped. He quickly calmed down and apologised.

"I know, honey, we-"

"No! Please, you h-have to listen to me! H-he has s-someone else!" The agents glanced around at the door and saw a woman stumbling in with a security officer clutching her arm and trying to turn her around. Emily studied the woman and gasped, racing over to the board.

"What is-" Morgan stared, but Emily cut him off by thrusting a photo in front of his face.

"That's Lydia!" She exclaimed, dropping the photo and hurrying out of the room and to the flustered woman before she was forced to leave.

"Hey. HEY!" Emily yelled as she pulled the officer from Lydia and flashed her badge.

"Please! Please, you have to listen to m-me! Please!" Cried an almost hysterical Lydia, who collapsed into Emily's arms with exhaustion.

"Lydia, I work with the FBI. It's okay, you're safe," Emily reassured her, trying to get her to stand without support.

"H-he has s-someone else. Jarvis! Dr. Jarvis! H-he r-replaced me," she sobbed.

"Did you say, Jarvis?" Morgan scowled. Lydia nodded tearfully.

"Hotch that's the guy who came in yesterday. He worked with Dr. Eton!"

A young female officer stepped forward a little guiltily.

"He spoke to me. He kept asking about agen-Dr. Reid," she said and Hotch turned on her.

"What? Did you not think it would be useful to tell us that seeing as he is currently missing," Hotch snapped and the woman shrank away.

"I-I didn't know..."

Morgan was already on the phone, pressing speaker as soon as he got through.

"Baby Girl I need you to find everything you can about a Dr. Jarvis. We need it 10 minutes ago; this guy has Reid," a tense silence followed, filled only by Garcia's sporadic typing and the team's nervous breathing.

"I have an address! Dr. Fraser Jarvis, he's the only one around the area and he worked with Eton. He's made loads of purchases of lab equipment, but I think he bought ingredients with cash, I've sent it all to you," Garcia rambled breathlessly. Rossi looked down at his phone.

"Marshal Avenue...that's less than 15 minutes away!" He exclaimed.

Spencer wiggled his fingers as he felt consciousness waking up his stiff body. His body felt different, as if he no longer fit into it. He pulled against the restraints and found that they had vanished. He pried his sleepy eyes open; the room was still dark so he shut them tightly again breathing heavily through his nose.

He didn't know how long he remained that way, but at some point a light flicked on, chasing away the darkness. He opened his eyes and looked around groggily. The light above seemed further away and the table seemed so much bigger. He jolted out of his dreamy state by a large face hovering above him.

"Can you hear me?" Dr. Jarvis asked. He shone a torch in Spencer's eyes leaving black splotches on his retinas. Jarvis lent down and pulled the tape off his face.

"HELP!" Spencer shouted, but he frowned at how high pitched and small his voice sounded. Spencer tried to roll away, but the older man put his hand on Spencer's chest and somehow held him in place. Spencer's brow furrowed more as he looked down at Jarvis' huge hand. He gasped when he saw that the shirt he had been wearing was practically falling off him and he wasn't even wearing his trousers or shoes anymore.

"What have you done?!" Spencer squeaked. Jarvis was examining Spencer and he let out a sigh.

"I can't accept this. You failed like the rest. Oh, and I had so much hope for you," Jarvis shook his head and picked Spencer up.

Reid yelled in embarrassment, but the doctor seemed to pick him up easily, ignoring his cries.

"Let me go! 'Top!" Spencer panicked when he realised he couldn't pronounce 'stop' properly.

"I'm sorry, Kid, but I expected you to work. I guess I've got to track down Lydia again." He walked into an office and set Spencer down on the floor, before grabbing some duck tape. Spencer saw the gun on the desk and struggled to his feet, rushing forward to grab it. He tripped on his socks which had grown to around 5x the size of his feet. He landed painfully on his hands and knees.

Jarvis turned and rolled his eyes as the child got back to his feet and reached the desk.

Spencer jumped up but realised that the desk was too high for him to reach for the gun. He whipped around and saw the doctor with duck tape in his grip.

"Don't fight this," Jarvis mumbled, but Spencer refused to give in. He ran as fast as he could around the desk, he got to the other side and saw the door. Just as he was about to make a dash for it he felt rough hands grabbing him. He screamed loudly before tape was slammed over his small mouth.

The team minus Reid stalked up to the door, their guns at the ready. Hotch knocked and called out for Dr. Jarvis. With no reply he nodded to Morgan who kicked the door down. The lab became filled with 'clear's from each room as the BAU made their way through; looking for their young genius.

"This one's locked!" They all followed Rossi's voice to a door with a danger sign over the front. Morgan took the courtesy of kicking that door down too.

They filed into the well-lit room and saw the metal table in the centre; the sort of table used in surgery.

JJ holstered her gun and rushed towards the table, despite Hotch's protests. She lifted the converse up and examined the scuffs that she herself had witnessed being created. His trousers were also discarded on the cold metal.

"Spence?" She called, her eyes filling with tears. A high pitch scream echoed through the building and the team raised their guns again.

"It came from in there," Morgan pointed out the office door, light spewed out from under it. A muffled cry leaked from behind it and Morgan raised his gun before kicking the door down.

Jarvis jumped back from Spencer when he heard the door crash open. Spencer trembled on the floor, his arms wrenched behind his back and held there with duck tape. He sat on his knees, his eyes closed so he didn't see the gun barrel that Jarvis had been aiming at him.

"Drop the weapon!" Hotch snarled raising his gun at the doctor. The doctor's weapon clattered across the floor and he raised his arms up weakly.

"Don't shoot!" Jarvis cried. Morgan holstered his gun and yanked Jarvis' arms behind his back and cuffed them.

JJ rushed straight to the crying boy, undoing the duck tape gently as not to irritate his delicate skin. As soon as he was free he wrapped his arms around JJ's neck and she felt hot tears seeping into her shirt.

"Where's our agent!?" Hotch spat. Emily knelt down and took the tape from the toddler's face, which was partially buried in JJ's shirt.

"It's okay, sweetie," she cooed, gently rocking the trembling boy. She barely noticed the fact he was wearing a huge shirt and big odd socks that didn't fit his tiny feet.

Jarvis laughed and they all turned to him, their faces contorted in rage.

"Where is Dr. Reid?" Rossi demanded.

The toddler pulled his head from JJ's shirt.

"I'm hewe."

Phew! That was a mouthful. I wanted to get to the real plot of this story straight away so I needed to get the case and the reason why Reid was de-aged out of the way.

Please leave a review and tell me what you thought, I can't believe I actually posted a de-aged fic! I was so anxious and then I just thought 'What the hell' and made a new story.

This week has been so...I don't know how to describe it? Empty? I haven't posted for what feels like forever!

Sorry if this seems rushed, I guess I got a bit excited today!

Thank you for reading, please favouite, and alert if you want to be told when I update, which should be pretty regular... hopefully.