Chicago Fire Boss and Jesse Spencer Explain Matt Casey's 'Bittersweet' Exit

[Warning: The following contains spoilers for the 200th episode of Chicago Fire. Read at your own risk!]

Chicago Fire showrunner Derek Haas might be as upset as you are about the fact that his leading man, Jesse Spencer -- a.k.a. Chicago Fire Department Captain Matt Casey -- has officially said his goodbye to the series in its landmark 200th episode.

"I hate that Jesse's leaving," Haas admitted in a small press conference with reporters this week.

The episode, which saw Casey decide to leave Firehouse 51 to take care of his late best friend's two sons -- whom you might remember from the pilot of the series, which aired all the way back in 2012 -- in Oregon. Casey, who'd finally decided to embark on an official relationship with paramedic Sylvie Brett (Kara Killmer) after a years-long flirtation, will continue to be a presence on the series as he and Brett have decided to date long-distance, but as of right now that's the last time we'll see him on screen.

Naturally, it was a difficult episode for Haas to write, he shared with reporters while praising former House star Spencer for his decade of work on Chicago Fire.

8 Chicago Fire Moments That Made Us Love Matt Casey

"He's been incredible from day one," Haas said. "I remember when he walked into the audition room and I thought, 'We have a show that's gonna go a long time now.' He's been incredible since the first day of the pilot to right now, and one of my favorite people beyond acting. It's not often you want to hang out after work, and yet any time I was in Chicago I would call Jesse and say, 'Let's get together.' I have very bittersweet feelings, or just bitter feelings, but the episode I thought turned out really well and I just want to thank Jesse publicly to everyone for ten years of amazing service and friendship and acting and making this show incredible."

Read on below for what Haas and the man of the hour, Spencer, had to say about the emotional goodbye, long-distance relationships, and the possibility of a FaceTime cameo. Chicago Fire airs Wednesdays at 9 p.m. on NBC.

On deciding to leave Chicago Fire after nearly a decade:

"I realized I've been doing TV for a long time. I added it up and I think this year is my 18th year of network television straight, because I went straight from House into Chicago Fire. We were coming up to the 200th episode and so I called Derek and broke him the news [that] I thought it was time to leave the show, and he agreed that we should at least get Casey to 200 episodes," Spencer said. "It was a difficult decision, because I've loved the show from the start, but there [are] other things that I would like to do in the future, and there's some family that I need to take care of, and 18 years is a long time. That's a long stretch."

On the future of Brett and Casey now that they're separated by half the country:

"We'd been establishing this relationship for three years and we finally just got there," Spencer explained, acknowledging that the couple's slow-burn romance had just started to smolder. But Brett understands that Casey is leaving for the right reasons, so the two will make it work. It was hard, though, because Spencer and Killmer get along well. "I really like Kara. We've established a really, really nice relationship. I loved working with her. We got on so well. And, you know, there is the chance that I will come back, too. We're sort of toying with the, you know, 'Will Casey come back?' If that's a possibility. [Derek and I] talked about that, and that's a possibility for me too. I think it was written really well into the episode because they're trying to make this relationship work. But they know that he's leaving, so they're sort of saying nothing's going to change."

Added Haas, "We're going to keep it alive. We're in a day and age where, because of FaceTime and easy airline tickets and phone calls, [they can easily keep in touch]. I was telling Kara, like, I'd go off for six months to do a movie when my kids were little, but that's just part of the world. Nothing changed [when I got back]. And so this is a three-year commitment Casey's making but hopefully, we'll see him before those three years are done."

On the possibility of Spencer returning sooner rather than later for a cameo:

Spencer's presence will be felt, but you will definitely not see his face in any future episodes -- yet. Said Haas, "Look, Jesse's been more than generous, more than generous, so we didn't want to [ask him to do that yet]. I'm sure I'm gonna hit him up. But for now, he's finished for a little bit." But, Haas teased, "We are going to hear his voice after the 200th."

On the last scene Spencer filmed as Casey:

"The last scene we filmed was on the burn stage," Spencer recalled. "It was hard, there's no doubt. It was hard to film that. There was, I guess, a strange feeling on set, but a happy feeling on set. It's bittersweet. And then someone's headlamp went out and -- props is amazing on our show, by the way, before I say this. Props is there with everything. And for some reason, a battery was missing."

While they waited for the new battery, "Everyone just started hitting [some poles on the set] and chanting, and it sort of became this semi-pseudo tribal send-off for me. It was awesome. Everyone was sitting outside the stage, because it's raised up and it's got this big hollow sound, and it was something else." Afterward, Spencer said, came the 200th episode cake-cutting and emotional tribute speeches from his castmates.

On Casey's emotional goodbye to the firefighters of Firehouse 51:

"Every now and then you write scenes that you want the cast and crew to hear what's going through your own head, and I don't want to talk too much because I might get emotional," Haas said as his voice started to break, "but you get to put it into a way better speaker than yourself's mouth, Eamonn Walker, things that you wanted to say to them. So that was a really difficult scene to write."

In fact, he placed the scene at the close of the episode because "Jesse meant so much to me I wanted to end the episode with that. I never do a preamble in a script, but in this one, because it was the 200th episode, I had a little preamble in the script about what the crew and the cast and everybody mean to me, because it really is special. I don't know that it'll ever happen again like this."

Chicago Fire continues Wednesdays at 9/8c on NBC.