Flashbacks
Jake: You're with Teddy and I'm going undercover.
Severide: Come on, Shay!
Lansing: She didn't make it.
Present day
Jake Peralta is undercover as a mob member.
Jake: Although the meatballs were a little dry.
Holt: Dry meatballs. That's Peralta's signal. Let's go!
Terry: Let's go! Let's go!
Voight: Go, go!
Terry, Voight and some other members raid the area.
The following day
Boden: Look who's back.
They all cheer.
Jake: Thanks, guys.
Herrmann: Welcome back, man.
Jake: Thanks, man.
Casey: Welcome back.
Jake: Heard you proposed.
Casey: I did, have yet to get an answer.
Everyone else from the house gathers around, they cheer again when Mills returns from his recovery.
Herrmann: Welcome back, Mills.
Mills: Thanks, guys. Jake, just got back from undercover assignment.
Jake: I did.
Sloan: Jake, welcome back, my boy.
Jake: Thanks, Adrian.
Sloan: And Mills, same.
Boden: Mills, go up with Peralta, let the cops know you're back.
Jake: Not going up quite yet, a new cop came with me, this is Sean Roman.
Boden: That's right.
Herrmann: Atwater got promoted to Intelligence.
Mouch: Burgess needs a new partner.
Jake: This is him. Adam's gonna be jealous of you.
Sean: This unit is my permanent home.
Boden: Nice to meet you, Sean, we are with the Fire Department.
Sean: Thanks.
Jake: Now we're going up.
Jake, Mills and Sean head up to the police floor.
Lansing: Our boys are back!
Everyone cheers.
Jake: Thanks, you guys, this is Sean Roman, Burgess' new partner.
Adam: Nice to meet you, Roman, Adam Ruzek.
Sean: Peralta warned me about you.
Charles: Sean, welcome to the unit.
Sean: Thanks.
Jake: Also welcome back to Mills.
Mills: Thanks, man.
Terry: Welcome back, both of you.
Lansing: Welcome back, boys.
Holt: Briefing room, now. Mills, welcome back and join your colleagues.
Everyone goes into the briefing room.
Holt: First up, welcome back to Jake Peralta from his undercover gig.
Everyone cheers.
Voight: Welcome back.
Holt: Detective Lindsay has an appointment, she will be in later today.
Amy: I need her help.
Holt: And finally this is Sean Roman, Officer Burgess' new partner.
Sean: Jake already introduced them to me.
Holt: Peralta, you probably noticed one less familiar face when you were visiting the firefighters.
Jake: I noticed a few, where are Dawson, Blair and Shay?
Lansing: Blair accompanied Erin, Dawson's visiting a friend, and this is very sad, Shay died.
Jake (tearing up): Copy that.
Terry: Also, her replacement paramedic will be here later today.
Jake: Thanks, I'm gonna talk to Severide later.
Lansing: Figured you would say that. He's AWOL.
Charles: Also, Ruzek and I gotta work on this case.
Adam: This is a very coveted case, glad we got it.
Lansing: Dismissed.
Jake: I expected Erin to see me the second I step foot in the precinct, she will see me the second she steps foot in here.
Lansing: She and Kelly are dating.
Jake: I'm gonna go talk to Dawson and Casey tonight.
Lansing: You, Casey and Dawson have been close lately.
Jake: Yeah. And Shay, completely unexpected, out of the blue.
Lansing: You should have seen it.
Jake: I should have.
Lansing: Everyone tried as hard as they could.
Jake: Kinda hard. I know Jin died, that was sad as well.
Voight: Peralta, we need to talk.
Jake follows Voight into the evidence room.
Jake: What's going on?
Voight: I'm sorry about Shay, she was a very big part of your life.
Jake: Really big part.
Voight: Now, you have to wait on calls, because no open cases yet and all paperwork is done.
Jake: Copy that.
Voight: Also Holt wants you with the firefighters right now, update us when the new medic arrives.
Jake: Copy, Sarge.
Jake revisits the firefighters.
Gabby: More time with us.
Boden: Holt sent him down here.
Jake: Spot when the new medic arrives.
Casey: Makes sense.
Jake: I did actually want to talk to Dawson.
Gabby: You found her.
Jake: What about your visit?
Gabby: Cut it short.
Jake: You do need to mourn.
Gabby: Shay was one of my best friends.
Lansing (on radio): Peralta, Teddy wants to talk to you.
Jake goes down to the 2nd floor.
Lansing: He's right here.
Jake: Teddy.
Teddy: Jake, the new medic should be here soon, they need you up there, we have a big problem, Shay may have died, same with Jin, Welch is targeting us.
Jake: Son of a bitch.
Lansing: Tommy Welch is the worst firefighter in the world.
Jake: We really hate that guy.
Firefighter area
Casey: Welch is a very bad guy.
Sloan: We want him out.
Jake: He's only around for a temporary time.
Casey: Thank god.
A woman walks in.
Jake: Looks like a new face.
Boden: New medic, nice eye.
Brett: I'm Sylvie Brett, new paramedic for 61.
Boden: Chief Boden, Detective Peralta.
Jake: NYPD.
Brett: Floor full of cops up there, I take it.
Jake: Yep. I gotta go.
Jake goes down to the 2nd floor and Lansing's office.
Jake: Captain.
Lansing: Peralta, what brings you down here?
Jake: The new medic just arrived, the name is Sylvie Brett.
Lansing: Sylvie Brett, you sure about that?
Jake: I am.
Lansing: Boyle's gonna be shocked.
Jake: They have history?
Lansing: They do.
Jake: Let's tell him.
Jake and Lansing go up to the fourth floor.
Jake: Charles, can we see you for a minute?
Charles follows the pair into the evidence room.
Charles: What's going on?
Jake: The name Sylvie Brett mean anything to you?
Charles: It does, why?
Lansing: She's Shay's replacement.
Charles: Oh, man.
Jake: Know her?
Charles: Grew up together.
Lansing: This is a very big deal for you.
Charles: I'll talk to her when Truck and Ambo go out on a call.
Jake: Got it.
Radio: Truck 81, Squad 3, Ambulance 61, Battalion 25, person trapped.
Lansing: Which is now apparently.
The units arrive at the call.
Boden: Truck, ladders and aerial.
Casey: Herrmann, Mouch, Otis, straight ladder, Cruz, position the aerial.
Sloan: Mills, with me, Tony, Capp, Newhouse, climb up and save the guy, police, security and breach.
Holt: Got it.
Boden: Ambo, set up triage.
Lansing: Move it!
They manage to succeed at the scene.
At the 99
Charles: Look who's back.
Everyone cheers as they see Erin.
Voight: How well are you?
Erin: Very, all good.
Jay: Perfect.
Lansing: This is Sean Roman, our newest police officer.
Erin: Officer Roman, hope you help us serve.
Sean: I will.
Erin turns around as she sees Jake, she then becomes ecstatic.
Erin (happily): What are you doing back here?
Jake: Undercover mission is done.
Lansing: Someone got away, Freddy Lombardi.
Jake: The worst of the guys.
Alvin: I crossed paths with him sometimes. He is a really bad guy.
Jake: Let's get him.
They bust through the door as Jake, Alvin and Lansing have guns out.
Lansing: NYPD!
Lansing goes through the kitchen.
Lansing: Clear!
Jake goes into the bedroom.
Jake: Clear!
Alvin: Clear!
None of them spotted Freddy.
At the 99
Voight: Freddy was nowhere?
Jake: Couldn't find him at all.
Lansing: Nothing we could do.
Holt: The FBI's still after him.
Lansing: So focus very hard on your other cases.
Jake: Got it, guys.
Charles: She changed in a good way.
Lansing: How good?
Charles: Really good.
Holt: How do you know the new medic?
Charles: We grew up together.
Amy: I would never have you pictured as a small-town boy.
Lansing: Same here.
Antonio: And here. If I'd have anyone here pictured as a small-town person, it's Ruzek.
Adam: I'm a city boy.
Holt: Everyone, this is Nadia DeCotis, our new phone operator.
Lansing: Make sure to give her a warm 99 welcome.
Nadia: Glad to be here.
Holt: Welcome to the 99.
Voight: Better make us proud.
Nadia: I will.
Erin: Glad you're here.
Jake: Just got something about Freddy's girlfriend, Bianca. We just got the address.
Holt: Go and take Boyle with you.
Jake: Copy that.
Lansing: I can go as well.
Alvin: Voight also assigned me to the case.
Later
Jake: Freddy hopped on the plane to Barbados and he got away.
Voight: Son of a bitch.
Lansing: Should've known this would happen.
Holt: He got away, not cool at all.
Jake: Can't believe it.
That night at Shaw's
Everyone: Surprise!
Jake: What! No way! Charles, you tricked me.
Holt: Boyle told you.
Jake: Without any prompting.
Holt: I'd like to say something, Peralta, your six-month absence was noted. Drinks are on me, two-drink minimum per person, your guests will pay their own tab, valet parking not included, tomorrow's briefing will be 15 minutes earlier than usual and I'm very proud of you, Peralta.
Lansing: Sometimes you have to go undercover, it could be short, it could be long, it could be in between, it could be anytime, but when you get out, you can begin your normal life again, it could be good, it could be bad, Peralta, your bust was one of the biggest RICO busts in history. Cheers.
Everyone: Cheers.
Jake: Hey, got you a drink.
Amy: Thanks.
Jake: Listen, I know you're with Teddy, I'm not trying to change that, there's stuff I can't control. But what I said this morning was a lie.
Amy: Well, thank you for saying that. Just as long as we're clear that I'm with someone and nothing is gonna happen.
Jake: "I'm with someone, nothing's gonna happen." Name of your sex tape.
Charles: There she is. Everyone this is the newest member of the fire team, an old friend of mine, Sylvie Brett.
Brett: Thanks, Chuck.
Lansing: Captain Lansing, this is Sergeant Voight and Detective Halstead.
Brett: Guys, incredible to meet you.
Everyone gets on well with her, except for Jake, who worries that Charles might prefer her over him.