Disclaimer: I do not own any part of Rizzoli & Isles. The characters belong to Tess Gerritsen, Jan Nash, Janet Tamaro, and TNT. I am in no way profiting from this. It's just for fun.

I also don't own any part of the Terminator movies, just using it for inspiration. The plot, without giving too much away, will have a couple similarities to the first film. But a vast majority of this fic will be very different than the films. I'm not sure if this idea has been done before, but I hope you'll still enjoy this. :)

Big thanks to MissToastie (aka sashaalexanderisalesbianatheart on tumblr) for helping me figure out a title to this. Until last night, this was just called "Rizzles Unnamed Terminator AU" How awful that would've been!

No beta. All mistakes, if any, are mine.

Time Between Us Ch. 1

2035, Underground Resistance Base

"Hey, watch it!" A soldier shouted as one his own, young Barry Frost, ran and shoved his way through the crowd. He paid no mind to him, his panic distracting his thoughts as he barreled down the hall.

'Shit. Shit. Shit.' Frost cursed to himself as a fresh bead of sweat rolled down the side of his head. 'Need to get to Jane and Cavanaugh!'

His fellow soldier and commander were unaware of the bad news, too busy celebrating their recent victory against SkyNet and the terminators.

"You've had some pretty close calls there, Rizzoli." Sean Cavanaugh commented as he filled a glass of scotch, then handed it to her.

Jane Rizzoli's eyes went wide as she accepted the liquor. "Whoa, where'd you get this?"

Cavanaugh smirked. "Been saving it for nearly 20 years since this shit started, wanted to open it when we won the war... To our victory. Hard fought and well deserved." He clinked his glass with hers, and they both took a sip.

"Damn, that's good." Jane hummed as the smooth liquid went down her throat. "I've never had hard liquor before... Only a few beers. Can't believe you managed to save this all these years."

"Your tolerance won't be so good, then... That's strong stuff, kid." He chuckled before taking another swig, savoring the sweet taste of alcohol.

"I may only be 20, but can out drink you anytime old man."

"Yeah? Well, we'll see about that won't-" He was interrupted when a panting Frost came bursting into the room.

"Frostie! Come have some of this, it tastes great." Jane then saw the expression on his face. "What's wrong?"

"Sky... SkyNet..." He panted out breathlessly. "We're fucked."

Jane stood up and placed the glass down on a table, grave concern immediately etched across her face. "Calm down and tell me what happened."

Frost caught his breath to explain the situation. "There's still a few terminators left... We didn't destroy them all."

"Ok, so? We just go hunt the bastards down. War's over, man..."

"No! The remaining terminators had some machine they were protecting. It was off the list of their known locations. Me and some scouters were chasing a few of them and discovered it."

"What kind of a machine?" The older of the three asked, coming from behind his desk to stand directly in front of his soldier.

"It's some kind of time machine." Frost elaborated. "Based on the information we recovered, it looks like they sent one of themselves back."

"Back?" Jane wondered in confusion. "This doesn't make any sense, time machines don't exist."

"You're not listening to me!" Frost interrupted her with a frantic shout. "They sent one back in time to kill the Doc."

The blood drained from Jane's face. "Is that even possible?"

"My dad didn't think computers becoming self aware was possible, but look what happened."

"Fuck..." Jane ran a hand through her thick black curls. "We need to do something. If they kill her, then this victory was pointless. We need her alive."

"What do we do?" Her comrade asked, looking between the two for an answer.

"One of us goes back, try and stop the terminator from killing her."

"You're right, Jane... That's the only way we can have a hope of stopping this for good. But who goes back?"

"I will." Jane volunteered, not one ounce of fear obvious in her voice.

"Jane..."

She turned to her commander. "Sir, I was the one who led the final attack on their base. I helped then and I can help now. Let me do this. You know I'm the best for the job."

Sean scratched his head, contemplating an answer. "But the risks..."

"I'm fully aware there's risks. But we don't have time to worry about this... She could be in danger right now."

"Alright..." He reluctantly agreed, knowing she was right. "I want to check out this machine myself first, then we inform the troops. They're gonna need a heads up in case things go wrong."

"What the hell are you talking about? SkyNet was destroyed! The doctor made sure of that." A soldier yelled loudly amongst the gathered crowd, causing the others to yell too.

Korsak, Cavanaugh's right hand man, whistled loudly to get the soldiers attention. "Listen up! We were just as shocked as you are... But we have a plan. Lieutenant Rizzoli has volunteered to go back as well, to try and stop anything from happening. The machine that terminator used to go back appears to be in working order, so she's leaving as soon as possible."

Jane stood with her arms by her side, patiently waiting while things were being explained. Her eyes scanned the group of men and women, they all looked at her like she was crazy. None of them had the courage to back. Truthfully, neither did she. But she knew this had to be done. She has a family to think about.

'Crap...' She thought to herself. 'I need to go find Tommy and Frankie to tell them. Man, this isn't going to be easy.'

While Korsak and Cavanaugh did their best to explain the crucial mission, Jane slipped away to her private quarters. Her younger brothers were there, reading old comic books she found on a scavenging mission a few years back.

She knocked on the door before entering. "Hey, guys... Can I talk to you for a second?"

"Janie, about time you showed up." Frankie teased his older sister. "Tommy is trying to say someone ate his share of food, but he already scarfed it down hours ago."

"I did not! Someone must've taken it." Tommy's eyes narrowed at his twin brother. "Maybe it was you."

Frankie pushed his shoulder. "No I didn't, tell him Jane."

"Boys! Knock it off." Her stern voice made them both sit up straight. "I have to talk to you about something serious."

"What's up, sis?" Tommy asked, instantly worried.

"I... I have to go on another mission."

"But I thought we won the war? Because Doctor Isles created that virus, then you and your friends crushed the terminators."

"I know, Frankie... I know. We did. Well, we thought we won. But it turns out the war isn't over just yet. One final mission, and it will be. I promise."

"Ok, but you'll be careful... Right? Come back real fast like always?"

The words stung Jane deeply, breaking her heart. She shook her head. "I'm sorry, but... I can't come back this time."

"Why not?" They both asked at the same time.

"I need to go back in time, to stop a terminator from killing Doctor Isles... But the machine used to go back, it's only a one way trip."

"But..." Tommy's lip quivered. "Why do you have to be the one to go? Why can't someone else do it?"

"I'm the best candidate for the mission, I don't want some rookie going and possibly making things worse. I have to do it."

"Jane, you can't go. We need you!" Frankie started crying, and Jane pulled both of them into a hug.

"I know you do. But this is the best way I can protect you. By making sure this thing is over for good."

"Won't we ever see you again?" One of her brothers sobbed into her chest. She couldn't tell which, the voice muffled by her shirt and the sound of them crying.

Jane didn't know the answer, so she went with what she could only hope for. "I'll try my hardest to get back here, and if I can't... Then I'll just have to wait a while to see you both again."

"Please don't go..."

"Frankie, I have to. I'm so sorry." Jane squeezed her younger brother tighter.

"When do you have to leave?"

She checked her watch and cursed in a whisper. "Damn it... I have to leave now."

"What? No! Don't!" Both Tommy and Frankie begged, desperately clinging to their sister.

"I have to..." Jane started crying.

"Why can't Frost go? You said he's the best soldier the Resistance ever saw!"

"He's more of a tech guy than a fighter... I'm sorry." Jane apologized again. "I need to go now, you can walk with me to the station but then you have to come back here."

"Who's going to take care of us?" Frankie wondered aloud as they pulled away from the hug, ready to leave their room.

"Well... Frost, for one. Korsak and Cav will be there for you, too. Plus the entire Resistance will have your back. You'll never be alone or unsafe, I swear."

"We don't want them, we want you!"

"I know." Jane took their hands and led them down a long corridor, heading towards where she was supposed to meet Frost.

"What's the plan, partner?" Frost offered a small smile, though there was only sadness behind it.

"I want you to have Martinez and his squad go back to the base and the surrounding areas. Make sure you all hunt down every single last terminator, so they don't try and retaliate." Her partner gives her a firm nod. "Good... I've already discussed this with Cav. You're going to either deactivate or destroy the time machine as soon as I'm gone. And all files that relate to it."

"What? Why?"

"Just in case they try this again. I want me and the terminator to be the only ones back there."

"But what if..." The soldier looked down at his feet. She knew what he meant.

"What if I fail?" Jane asked anyway. "Wait just long enough to see if I'm successful, then decide between destroying it or deactivating it. I'm sure whatever happens here, you'll all think of what to do. Right?"

"Yeah..." He gave her another nod, this one much more solemn, then looked at her younger brothers clutching at her pant legs. "And these two?"

"Take care of them. Guard them with your life, please."

"You have my word." Frost looked her in the eyes and tried his hardest to not cry or become emotional, but this is his best friend. The woman he fought side by side with many times over the years. He shed a few tears and cursed "Damn it, Jane..."

"Come here." Jane ordered, and hugged him closely.

"Rizzoli, it's time." A soldier announced from the distance.

Jane pulled back from the hug and wiped away fresh tears in her eyes. "Well, this is it." She knelt in front of her brothers to say her final words to them. "I'm gonna miss you guys, so much. You be good for Frostie, huh? Promise me you'll be on your best behavior."

"We will." Frankie and Tommy promised, their little jaws clenched tight. Frost stood stoically behind them, his hands on their shoulders, offering what little support he could at the moment. He too was struggling with this.

Jane gave them both one last hug before parting ways with her brothers, and before turning the corner, she looked at them. "I love you both."

"Jane, we have a problem."

"You mean besides the terminator situation?" Jane laughed while gearing up by the machine.

"Um..." Korsak's cheeks flushed a bright shade of pink. "Well, there's this thing about the machine."

"Ok..."

"We went through the notes and files, and it appears that nothing dead can travel through time."

"That's good news, wouldn't want a zombie apocalypse on top of a machine versus human war..." She continued joking, trying to lighten the mood with her good friend.

"That's not it... You can't go back with weapons. Or clothes."

"What?!" Jane shrieked in anger.

"Sorry!" Korsak apologized, with a hint of a smile gracing his face. "I didn't design the machine."

"Ugh... This is just great. I gotta go back in time naked and without guns!"

Cavanaugh came over with a woman trailing behind him. "Jane, I'd like you to meet Doctor Isles. She's the one responsible for creating that virus that helped take down SkyNet."

"Pleasure to meet you, Miss Rizzoli." The quiet doctor extended a hand. "Thank you for what you're doing."

"Thank you for creating that virus." Jane took her hand in her own, and heard a soft gasp escape Doctor Isles' lips. She quickly averted get gaze and took a small step back.

'What's that about?' Jane wondered, but shrugged it off.

"Have you read up on everything about her?"

Jane's focus returned to Korsak. "Yeah, I read her file on the way over here. She attended Boston Cambridge University, so I should start looking there."

"I frequently went to a bar called The Dirty Robber, you might have some luck finding me there."

Jane turned back to face the honey blonde woman, who was nervously twisting a ring on her finger. "I'll be sure to look for it. I'll take good care of you, Doctor Isles."

"Maura."

"I'm sorry?"

"Call me Maura."

"Maura." Jane smiled at her. Part of wished she could get to know this woman more, aside from what's she heard, but she now realized that she had a chance to. "I need to be going now, but I'll see you later."

It was the first time in their brief meeting that Maura had smiled, and Jane was looking forward to seeing it again.

"Bye for now, Maura."

"Goodbye, Jane."

Jane shook her hand again, then walked over to the platform and began to undress, ignoring the whistles coming from a few men nearby. She kicked away her clothing before she knelt down on the cold metal.

"You ready?" Cavanaugh asked from across the room, prepared to press the necessary buttons to send her back in time.

"As I'll ever be..." She muttered under her breath. "Go."

"Good luck, Rizzoli."

Jane clenched her fists as a bright flash of light surrounded her, the platform beneath her shaking. "Here we go..."

Ok, that was the first chapter! I hope you enjoyed it. There's going to be so much more to this story, so I hope you stick around. I'll try to update as often as I can. Any confusing parts, with the whole time travel thing or certain characters, will be explained in later chapters. Don't forget to review so I know what you think. :)