Where does Kelly Severide (Taylor Kinney) go from here?

On Tuesday's two-hour crossover between Chicago Fire and Chicago P.D., Severide prepared himself to go all in with his bone marrow donation, only to get the devastating news that the patient, Anna (Charlotte Sullivan), took a turn for the worse and the donation will be impossible.

The P.D. gang comes onto the scene after Severide's car is involved in a fatal hit-and-run — with the problem being that, after drowning his sorrows about Anna's deteriorating condition, Severide can't remember whether or not he was behind the wheel... Or who might have been if he wasn't.

Though it eventually becomes clear that Severide was the victim of a car theft ring, his problems don't end there. He's developed quite an attachment to Anna, and also deals with the rude awakening that he has no idea who to put down as an emergency contact on his medical forms. (He ends up landing on Stella Kidd [Miranda Rae Mayo], who's fully supportive of his decision to donate.)

But Severide isn't the only person in the house dealing with a personal crisis. Casey (Jesse Spencer) and Dawson (Monica Raymund) agree to meet with Louie's biological father and discover that he's actually not a bad guy. He hasn't been in Louie's life until now because he broke things off with Louie's mother after a fling upon realizing she was a drug addict, and didn't even know he had a child until she got in touch with him recently asking for money. As a result, he has a very credible claim to take custody of Louie, which obviously puts a rather large dent in Casey and Dawson's plans for domestic bliss. But the fact that he skips out on his planned introduction to Louie doesn't bode well.

On the P.D. end of things, Burgess (Marina Squerciati) doesn't exactly get a warm welcome to Intelligence, with Ruczek (Patrick John Flueger) actively avoiding her and her new partner/mentor, Olinsky (Elias Koteas) flat-out telling her he doesn't think she's qualified for the job.

Lindsay (Sophia Bush), meanwhile, discovers that Voight (Jason Beghe) and her mother go back even further than she originally thought, and grapples with the decision about whether or not she wants to meet her father.

TVGuide.com chatted with Chicago P.D. showrunner Matt Olmstead and Fire executive producer Derek Haas about what's next for Severide, an upcoming "surprise" for Casey and Dawson, whether Olinsky will ever warm up to Burgess, and more.

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Severide seems to have hit an even lower point than we saw in the midseason finale. Is that fair to say? And what, if anything, is going to pull him out of this?
Derek Haas:
What we're looking for is Severide looking into that mirror and seeing a future for himself that looks a lot like Benny, and not liking that. And especially this kind of wake-up call of these two episodes push him further. He's going to go a very painful and far distance route to try and do whatever he can to save this girl, beyond what is probably recommended. So that's coming in the next episode.

Is the "emergency contact" moment a sad realization for him?
Haas:
That was two things for us. It was part of this existential crisis, for lack of a better word, that he's having. A definitely self-reflective crisis that he's having. But it also served the purpose of reminding us that Stella and he are tight. We kind of let that drop after a few episodes this year, but it's something we wanted to resurrect and continue going forward, is that they have a kismet, a unique relationship on the show, and perhaps there's more to still explore between the two of them.

You had previously said that there might be a love triangle between Severide, Stella and Anna. Is that still the plan?
Haas:
That is still true.

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Casey and Dawson's adoption story also takes an unexpected turn, with the reveal that Louie's father isn't the deadbeat dad that most people probably assumed he is. How complicated is this situation going to get?
Haas: That's the goal, as writers, always to surprise the audience and slip expectations. Just when you think we're gonna zig, we zag. And certainly that's the case on the story of Louie's biological father. We want to keep playing with your expectations of who this guy is, what his motives are, how Casey and Dawson are going to react, and get as much drama as we can out of that situation. So, the story's not over, with what we show you in the crossover. But it will have an end, and hopefully we're going to surprise you on where you think it's going.

Switching to P.D., Lindsay learns that Voight and her mother go back further than she thought. Does any other information about their interactions come to light?
Matt Olmstead: Yeah, we really explore that going forward. The next three episodes, really, that's the arc for Lindsay and Bunny and her dad, who comes in out of the cold. And Voight's knowledge of this guy. A lot of secrets are revealed. Halstead gets caught in the middle, because he wants the old "trust but verify." Also, there's an instant dad who walks in. [Halstead] wants to make sure this is the dad. And does Bunny have a game running here? So it really impacts Lindsay, Voight, Halstead, and by extension, Bunny. It really comes to a head. But definitely the Lindsay-Bunny relationship, as we've explored over the years, we hit the tipping point.

Burgess and Olinsky are not off to a good start. Do they continue to butt heads?
Olmstead:
They continue to butt heads, but it's really not butting heads. It's Olinsky butting his head against hers, and her realizing, I can't return it, so to speak. So, we do have an endpoint there in mind, in terms of what happens with their partnership. But initially, he really does kind of go after her.

What does she have to do to prove herself?
Olmstead: She realizes, I have to take it, because if I go complain or break down in tears, I'm only confirming his suspicions that I'm not strong enough to be up here in Intelligence. So, he really kind of picks on her to see what she's made of, and down the road, she'll prove it or disprove it. But, we definitely wanted to explore that.

Does Ruczek defend her at all against Olinsky?
Olmstead:
No, he goes the opposite way. Ultimately, he gets there, but his initial reaction is to just run away from it. He doesn't want to deal with it. And so, she doesn't have a ready ally and a rock to lean on and support her. And she realizes, this guy still has feelings. Keep in mind, she's the one who gave the ring back, and maybe she didn't really kind of fully grasp the magnitude of what happened. Ruczek's reaction is to just not deal with it.

Anything else you can tease about what's coming up?
Olmstead:
We're very excited about Justice joining the fold. No spoilers yet, but I think you're going to see some Justice characters on the other shows, and I think you're going to see some of our characters on Justice. These crossovers aren't going away any time soon.

Chicago Fire airs Tuesdays at 10/9c on NBC. Chicago P.D. airs Wednesdays at 10/9c on NBC.