When Charlie Barnett’s character Peter Mills left Chicago Fire at the end of Season 3, it left fans of the One Chicago universe in shock. Mills, once a beloved and central figure in the show, had become a key part of the team. So why did the show choose to write him out? Barnett has since reflected on the decision that, at the time, left him “broken” but ultimately turned out to be the best career move he could have made.

In an emotional interview with Digital Spy, Barnett admitted how difficult it was to be written out of the NBC hit. “I really was sad to be let go. It broke me for quite a long time,” he confessed. Having been one of the original cast members, Barnett felt a deep connection to the show and never saw his time on Chicago Fire as a stepping stone. For him, it was home. But as the nature of television dictates, storylines evolve, and cast changes are often a part of that evolution.

Barnett later acknowledged that, while the exit was painful at the time, it ultimately proved to be a blessing in disguise. “You never really see the bad moments becoming the good. So I’m thankful,” he reflected. His departure opened the door for new stories and fresh characters, a decision explained by Chicago Fire executive producer Matt Olmstead. “It was solely based on bringing in new people for new stories,” Olmstead told TV Guide. He explained that keeping the original cast intact too long would have led to stagnant storytelling, and shaking up the dynamics was necessary for the show’s longevity.

While Peter Mills’ absence left a void, the show moved forward, and Chicago Fire continued to evolve. For fans, Mills’ departure was a hard pill to swallow, and his legacy is still fondly remembered by long-time viewers. However, Barnett’s career has soared in the years following his departure from the show.

After leaving Chicago Fire, Barnett found great success in a range of roles, showcasing his versatility. He received critical acclaim for his performance in Netflix’s Russian Doll, where he displayed impressive emotional depth and comedic timing. He also took on a darker, more complex role in You Season 2, where he played a love interest with emotional depth. Additionally, Barnett starred in Tales of the City, where he explored a character deeply rooted in community and self-discovery, further solidifying his range.

Barnett also joined the Arrowverse in the final season of Arrow, a move that marked another milestone in his thriving career. While his departure from Chicago Fire was painful, Barnett proved that resilience pays off.

Despite his successful career post-Chicago Fire, Barnett remains close to his Firehouse 51 family. He shared that he still keeps in touch with co-stars David Eigenberg (Herrmann), Joe Minoso (Cruz), and Monica Raymund (Gabriela Dawson), showing that the bonds formed on set extend far beyond the storylines.

Looking back, Barnett’s journey serves as a testament to the unpredictable nature of Hollywood and the power of resilience. From heartbreak on Chicago Fire to starring in hit series, Barnett’s departure was only the beginning of his career.