The Intelligence Unit's gain is Halstead's loss. Or will it be? After leaving the police to work for the Feds at the end of last year, Lindsay (Sophia Bush) came calling at Voight's door, hat beanie in hand, asking for her old job back on Chicago P.D. (Wednesdays, 10/9c, NBC). Sure, Voight (Jason Beghe) welcomed her back with open arms, but her return to her old stomping grounds will surely complicate her blossoming relationship with her former partner (Jesse Lee Soffer). So what's next for the fan-favorite pairing? Which familiar face is coming back into Lindsay's life? And who's Antonio's possible new lady love? Showrunner Matt Olmstead spills on what's to come:

Lindsay just asked to return to Intelligence at the end of the last episode so what is the trajectory for Linstead?
Matt Olmstead:
They're cut from a little bit different cloth than say Dawson and Casey. They're more of an immediate romance but when it's got to cool off, it's got to cool off quickly because there's no Voight looming over Dawson and Casey. And Voight made it clear he doesn't tolerate in-house romances, which is why they didn't do it and which is why when she was at Task Force, they jump on it, so to speak. But once she comes back, having just worked on a script where it's Episode 16, they're flirting in the coffee room and Halstead walks out and sees Voight watching him with a look that says it all. Like, I know what's going on here, and I warned you once. He makes a couple little side comments alluding to that, and Halstead and Lindsay scramble, like: What are we going to do? Either one of us is going to transfer out or we're going to have cool it off. How long they will do that - who knows? But it's not going to be one of those romances where one of them is staring over their coffee cup pining for the other and jilted. It's a mutually agreed-upon romance and a mutually agreed-upon cooling off of said romance.

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Was there any hesitation in pairing them together early in the show's run knowing how much the fans had been waiting for that?
Olmstead:
I think it was the right time. It's the second season. We were never going to do it and then we had an episode where she was reluctantly having to go to her 10-year high school reunion and he took her. We wrote it that way, but the actors really exceeded our expectations in terms of the chemistry. Right then we knew, "Well, come on. Eventually this is going to have to happen." If they're both single and there's this kind of simmering romance and once she goes to task force, it would be science fiction to not have them be together. It's a workplace romance, they have the opportunity to do it, they do so, but then they're both pragmatists and they both love working Intelligence, and they know it's not the time, because they want to have to leave and also they like working together. They like being partners. And that would end if they decided to come out as a couple.

What kind of obstacles will Voight face in the second half of the season?
Olmstead:
We've got a couple stories coming up. Lindsay's mom, Bonnie, comes back in the picture, who you can never tell if she's telling the right story, if she has as agenda and here's Voight, and he has to go back into protector mode and a be a buffer between Lindsay and her mom. Lindsay is a very tough girl who can handle herself in any situation, but she really kind of shrinks when her mom shows up. And she shrinks when her mom and Voight get into it, because it's like watching your parents fight when you're five years old. She doesn't have the ability to insert herself like she would in any other situation in her life. She lets her mom roll over her a little bit. So it's a great episode to see Voight defend Lindsay and it's a window into the past of how he basically raised her and saved her life.

And then there's another story with the original card holder. One of the mythologies of the show is Voight, every once in awhile, will give his business card to someone who he feels can make it if they call him one day as Lindsay did. And so his original card holder comes back needing help, so it's a little more of a window into his past.

Antonio has been struggling with his marriage. Will there be any resolution to that or continuation of that story?
Olmstead:
We've played it where he didn't want this to happen, but rarely do you have a mutually agreed-upon divorce. But it proved to be too much for his wife. We find him dealing with it. He's a loyal guy, a family guy. He's not out there tomcatting around town. ... But we do have a detective he used work to with in VICE. VICE has a special place in his heart. So here comes a woman who is also going through a divorce that he used to work with, and we're playing a little bit of a romance with her. It's also really great having seen it to see the character out with a drink in his hand. He deserves to have a good time too. He deserves to have a romance too.

The other relationship that has been big on the show is Burgess and Ruzek and they had that great moment after her shooting. What's next for them as a couple?
Olmstead:
You kind of stagger in sequence different relationships. While one is doing well in the show, one is normally not doing well. Right now we're playing the Lindsay-Halstead of it all, we're just playing that Burgess-Ruzek is going well, but it will pick back up again. ... They're definitely heading for conflict. What it is, we're still kicking that around.

Chicago P.D. airs Wednesdays at 10/9c on NBC. Are you sad about Lindstead?