Chicago Fire Season 12 has ignited a storm of emotions, delivering major shake-ups, long-awaited reunions, and heartbreaking exits that have left fans breathless. After delays caused by industry strikes, the flames roared back to life in January 2024—and Firehouse 51 hasn’t been the same since.

When we last left off, Season 11 ended with more questions than answers. Mouch had been gunned down in a terrifying call and rushed into emergency surgery. The screen cut to black before fans could find out whether he lived or died. Meanwhile, Casey made a surprise return and dropped a bombshell of his own—a proposal to Brett, reigniting a romance that once seemed lost to long distance and heartbreak.

But things weren’t just uncertain for the characters—behind the scenes, too, the cast was in flux. Kara Killmer, who plays Brett, is officially exiting the series in Season 12, as is Alberto Rosende (Gallo), whose emotional farewell in the season premiere was a gut punch for longtime viewers. Rosende shared a heartfelt message with fans, expressing how difficult it was to say goodbye and how proud he was of the story he got to tell.

On the flip side, Taylor Kinney’s Severide—absent since Episode 14 of Season 11—has finally made his way back, but his return is complicated. Though his “training program” in arson investigation was meant to be temporary, Severide didn’t come home when it ended. Stella Kidd, his wife and fellow firefighter, packed her bags and left Chicago to find him, setting off an emotional subplot that’s still unfolding in Season 12.

Rome Flynn (known from How to Get Away with Murder) has joined the cast as a new recruit in Episode 2, stepping into the chaos of Firehouse 51 as fresh energy meets raw emotion. His arrival couldn’t come at a more critical time, as the team continues to reel from recent losses and readjustments.

Season 12 is navigating uncharted territory, not just with character departures, but with legacy shifts. The original chemistry of Firehouse 51 has been tested, and the writers are clearly leaning into big swings: cliffhangers, surprise reappearances, and emotional breakthroughs.

And while Chicago Med and Chicago P.D. continue airing in the same night slot, it’s Chicago Fire that’s leading the charge in redefining what this franchise can be post-strike—with heavier stakes, deeper character arcs, and a whole lot of heartache.

One thing is certain: the fire hasn’t gone out. It’s only burning hotter.