This is my first attempt at POI fanfiction so I'd appreciate your thoughts and I hope you like it. Also posted on AO3.

Set early season 4 but goes slightly au from there (Shaw stays with the team).

Disclaimer: I don't own Person of Interest or the characters.

It took Shaw a while at first to figure it out, that her and Root were dating. Things between them had started as you'd expect, sexual tension climbing to the point where neither of them could deny it and they fell into bed together after Shaw had finally just grabbed Root and kissed her.

And that was all it had been at the beginning, just sex. Until it wasn't anymore. Until Root was spending the night at Shaw's place more often than not. When Root didn't only spend the night after sex, but would crawl into bed in the early hours of the morning after a long mission and wrap herself around Shaw and Shaw would let her. It was lazy afternoons and slow kisses and so much more than either of them thought they'd ever find with another person.

One day Shaw had finally asked Root about it, if she considered what they were doing was dating. Root had just laughed, said "of course, Sweetie," then given Shaw a quick kiss before they'd burst into the room they'd been surveilling to kneecap a few bad guys together.

X

It took the rest of the team a while longer to catch on that there was something going on between them. They all noticed the flirting, that was hard to miss, but other than that, nothing changed in their professional relationship, that the guys noticed anyway.

Harold had been the first to find out, and that was simply by accident. He was supposed to be out with Reese working a number but they'd needed extra equipment from the station. Root and Shaw had been there when he'd left, they had been working on a number of their own and finished earlier that day so he'd expected them to be long gone by the time he returned. Unfortunately for Finch, that was not the case. He stopped walking and his mouth dropped open at the sight that was in front of him as he walked into the station.

"Oh my," escaped from his lips, unheard by the distracted women in front of him. And they were definitely distracted. Root had Shaw pressed up against a nearby wall, bodies pressed tightly together as lips moved and hands roamed.

Harold heard a moan and he wasn't certain which woman it came from but he didn't want to stick around to find out. He turned abruptly and left, willing away the images that were now burnt into his mind. He wasn't going back in there, they'd just have to make do without the equipment they'd needed.

Finch hadn't told anyone what he'd seen but the next time he saw them together, he could now tell that something was different. Root still flirted heavily and Shaw still rolled her eyes but now he could see something softer in her eyes when Shaw looked at Root, something he hadn't noticed before and he knew now that whatever he'd seen that Root felt for Shaw, Shaw felt it in return.

X

Fusco was the next to find out and he's honestly surprised he hadn't figured it out sooner. Although, to be fair, he did think Root was crazy and that Shaw had more common sense than that. He and Shaw were on a stakeout when Shaw's phone had rung. He thought nothing of it until he heard, "I'll be home later," and, "no, don't wait up." By the time Shaw had hung up the phone, Fusco was staring at Shaw, mouth hanging open in surprise. Shaw was seeing someone?

Shaw just glared at him, daring him to talk and Fusco kept quiet for all of 30 seconds before he was talking, "so, who's the lucky guy?"

Shaw scoffed in response but before either of them could say more, Shaw's phone was ringing again and this time Fusco saw who was calling.

"What does Fruit Loops want?" he asked as Shaw answered her phone, giving him another angry look.

"What?" Shaw answered, and Fusco was glad her irritation was momentarily directed at someone else.

Fusco couldn't hear the other side of the conversation but was surprised when he saw a small smile appear on Shaw's face.

"Really, you called me back for that?"

Wait, does that mean she was talking to Root before too, Fusco thought.

"Ugh, fine, I love you too," Shaw said and if Fusco was surprised before, he's definitely shocked now. This time he could hear faint laughter coming from the other end of the phone before Shaw hung up.

"So, you and Root, huh?" Fusco asked, yet again unable to keep his mouth shut.

"You tell anyone what you just heard, I'll break both your legs, okay?" Shaw threatened. It wasn't like she was ashamed of Root or anything, she just liked keeping her private life separate from her professional one, which was difficult at times when you worked so closely with your partner.

Fusco grinned in response but nodded anyway, sure their secret wouldn't stay secret for long, especially not with Root involved and how closely they all worked. Then both he and John would be able to tease Shaw as much as they wanted.

X

Fusco had known about Root and Shaw for several weeks before Reese found out. Finch had called John in on an undercover mission and when he'd arrived at the subway station, he was met with Root's laughter ringing through it. He found Finch at his monitors with Root and Shaw standing beside him, both grinning while Harold looked concerned.

"I thought the mission was only for Shaw and I?" John asked when he was beside them, eyeing both Shaw and Root suspiciously as they grinned. Granted, they would probably shoot something tonight so he could understand why Shaw may be happy but it didn't explain what they found so funny, he'd never seen Shaw like this before.

"Why don't you tell him about the mission, Finch?" Shaw asked, still grinning which was slightly concerning to watch.

John looked at Finch for some clue as to what was going on.

"You and Shaw are going undercover as a couple," Finch replied, like that cleared everything up.

"You mentioned that before, and it's not the first time we've done that, "John replied, looking at Shaw now, trying to figure out what he was still missing.

"Not just any couple," Root replied, still grinning, "a married couple."

John still didn't get it.

"Oh, come on," Root continued when Reese still looked confused, "you two have no chemistry whatsoever, your cover will be blown immediately."

Now it made more sense what they were laughing about, and John felt slightly offended, he could handle anything on a mission.

"Yes, and they were suggesting a different undercover team for this mission," Harold replied, needing to hurry this along so they could get on with their mission.

It took John no time at all to figure out the team there were proposing and he was surprised Shaw seemed so willing to go along with it, unless she'd been laughing at how insane it was, "you two?"

"Why not?" Shaw asked immediately, almost defiantly, and John knew then that she hadn't been laughing at the craziness of the idea.

"Really? The two of you? Undercover together? No offence Root but don't you think that Shaw is likely to kill you if you have to spend so much time along together, as a couple no less?" They'd all seen the way Root flirted with Shaw and the reaction it always got, he couldn't imagine what would happen if they actually had to pretend to be a couple.

Root burst out laughing, Shaw looked surprised and Harold was suppressing a smile.

"What?" John asked, confused again.

"You do realise that Root and I have been sleeping together for months now, right?" Had he honestly not noticed?

"Oh," was John's only reply, not entirely sure now to respond to that. It did kind of make sense now that he thought about it, with all the flirting that wasn't exactly one-sided anymore and the slow friendship he'd noticed growing between them that was apparently more than he'd originally thought. And they somehow made sense together, he could see that just looking at them now, how had he not seen this before?

"We're dating," Root said, massive grin on her face as she looked down at Shaw.

"I hate that word," Shaw grumbled but she couldn't deny it. As much as she thought she'd never be in this position with someone else, here she was.

Root shrugged, "well, it's true, isn't it?"

"Yeah," Shaw admitted, smiling back, at Root and honestly, how had he missed this?

"Am I the last to know?" John asked, wondering how the rest of the team kept it hidden from him too.

"Yeah, I mean we weren't trying to hide it, you guys are just slow. Plus, I did threaten Lionel with broken legs if he repeated what he'd heard.

"What did he hear?" John asked, not entirely sure he wanted to know, it could honestly be anything with the two of them.

"She loves me," Root grinned again.

"Shut up," Shaw grumbled but everyone could see the smile she was trying to hide.

"Turns out Harry here walked in on us kissing though so it's not surprising he said nothing either so this was probably a better way for you to find out," Root replied while Finch looked extremely uncomfortable.

"So, you two can handle this mission then?" Finch asked, wanting to change the subject now, he really didn't want a reminder of that particular day.

Go undercover as a couple and shoot some people? This was a job that Root and Shaw were made for.