Sylvie Brett is Leaving 'Chicago Fire' to Begin a New Life With a Special Someone

Spoiler alert: This article contains spoilers for Season 10, 11, and 12 of Chicago Fire.

Just when things begin to go right for some of the characters in Chicago Fire, everything has to get more complicated. Characters come and go from Firehouse 51 all the time, and with 12 seasons under its belt, there's plenty of opportunity for some of our favorite characters to leave the show.

After Matthew Casey (Jesse Spencer) came back for a surprise turn, many fans expected a love triangle between him, Sylvie Brett (Kara Killmer), and her-now former beau Dylan (Christopher Allen). What does happen, however, is that Casey and Brett get engaged after he proposes in the Season 11 finale. The turn of events not only marks a new chapter in Brett's life, but it will also impact her role in the show. Scroll on to find out why Brett is leaving Chicago Fire.

During the Season 12 premiere titled "Barely Gone," Brett revealed she is leaving Firehouse 51 so that she and Casey can move to Portland together. There, they will embark on a new life journey as husband and wife. "Matt and I talked it through, and the truth is, we've waited long enough to be together full-time," Brett admitted during her conversation with Violet (played by Hanako Greensmith) and Mouch (played by Christian Stolte).

Although Brett will be leaving behind her Firehouse 51 family for good reasons in Season 12, it isn't the first time the words "Brett is leaving Chicago Fire" have been tossed around.

Despite Casey's return to the firehouse for an episode in Season 10, Brett's storyline has been relatively non-dramatic. But that all changed. When she filled in for her now-ex-boyfriend, Dylan, in the magic show, she bombed terribly. So we now know that Brett isn't meant to be a magician. But one of the things we love most about Brett is her dedication to the people and values she loves.

The promo for Season 11, Episode 20, titled "Never Make a Mistake," features a "Firehouse Feud" which Brett seems to be at the center of. She tells Chief Boden, "The first shift screwed up. They didn't replace the kits." And he simply responds, "They made a mistake." But because of that mistake, it seems like lives were lost, and Brett isn't having it.

"If you don't file charges for this, I will quit," Brett threatens as a shot of her packing up her bag in the locker room looms over us. It seemed very plausible that Brett could leave the firehouse because of this, but that would be a pretty devastating turn of events.

Luckily, fans were thrilled to see that Brett didn't need to leave the firehouse. However, the drama in her plotline was still brewing! By Season 11, fans were worried, yet again, that she could be leaving.

The teaser for the Season 11 finale showed that Brett was considering leaving to start a family, so it's no surprise that she acts on it in Season 12. And while some question how her adopting a baby will affect her relationship with Casey, we're not concerned. After all, he is father material.

Prior to fans learning Brett is leaving Chicago Fire, Kara hadn't shown any signs of her exiting the series. Not only did she post regularly about her time on the show, but she hadn't given us reason to believe that she would be leaving the franchise.

As of February 2024, it appears Kara has no other upcoming or current projects listed on her IMDb. While she hasn't provided a reason for her departure, we're guessing it isn't because of scheduling conflicts.

Catch new episodes of Chicago Fire on Wednesdays at 9 p.m. ET.