Over its remarkable 13-season run, Chicago Fire has been a cornerstone of NBC’s One Chicago franchise. With unforgettable emergencies, fiery drama, and deeply personal storylines, Firehouse 51 has become home to some of the most compelling characters on television. From original cast members to more recent fan favorites, these are the 10 standout characters that helped define Chicago Fire and continue to shape its legacy.
10. Darren Ritter (Daniel Kyri)
Though a newer face at Firehouse 51, Darren Ritter has quickly become a beloved part of the team. After being let go from Engine 37, Ritter was given a second chance by Herrmann and Mouch—and he hasn’t wasted it. His growth, kindness, and representation as a proud gay firefighter have added depth and warmth to the show. From nervous rookie to steady hand, Ritter has proven he’s here to stay.
9. Stella Kidd (Miranda Rae Mayo)
Bold, brilliant, and fiercely loyal, Stella Kidd joined the team in season 4 and quickly became a force to be reckoned with. Rising through the ranks to become lieutenant and leader of Truck 81, Kidd’s journey has been nothing short of inspiring. Her commitment to her community and devotion to those she loves, particularly her husband Severide, make her a key pillar of Firehouse 51.
8. Joe Cruz (Joe Minoso)
Cruz has evolved from a troubled youth into one of the firehouse’s most reliable veterans. Starting out on Truck 81 and later transferring to Squad 3, Cruz’s loyalty, humor, and emotional depth have made him a fan favorite. Through personal tragedy and triumph, Cruz’s dedication to his work and his growing family only endear him more to viewers.
7. Sylvie Brett (Kara Killmer)
Paramedic Sylvie Brett brought grace, compassion, and skill to Ambulance 61. Joining in season 3, she filled the shoes of the beloved Shay and made the role entirely her own. Whether handling high-stakes calls or navigating her complicated love life, Brett consistently embodied strength and empathy. Her season 12 farewell, leaving with Matt Casey and adopted daughter Julia, was the perfect send-off.
6. Kelly Severide (Taylor Kinney)
Severide’s passionate, often tormented journey has kept viewers glued to their screens since the very beginning. His deep bond with fellow firefighters, especially his complex friendship with Casey, has anchored the show. Despite moments of personal turmoil, Severide remains one of the most dedicated and skilled firefighters in the One Chicago universe.
5. Matt Casey (Jesse Spencer)
As the steady leader of Truck 81, Matt Casey was the heart and soul of Firehouse 51 for nearly a decade. Calm under pressure and loyal to a fault, Casey’s strong moral compass and leadership earned him the respect of everyone around him. Though he moved to Portland in season 10, his brief returns—including his wedding to Brett in season 12—proved how vital he remains to the show’s legacy.
4. Chief Wallace Boden (Eamonn Walker)
The commanding presence of Chief Boden provided the backbone of Firehouse 51 for over a decade. Protective, wise, and endlessly supportive, Boden led with integrity and heart. Though he stepped down as chief at the end of season 12, his new role as Deputy Commissioner ensures we haven’t seen the last of him.
3. Brian “Otis” Zvonecek (Yuri Sardarov)
Otis was the heart of the firehouse, bringing levity and loyalty to every episode. His tragic death in season 8 devastated fans and his fellow firefighters alike. Sacrificing himself during a deadly blaze, Otis’ final words to Cruz cemented his legacy as a true hero. His absence is still felt, and his memory remains a driving force at 51.
2. Christopher Herrmann (David Eigenberg)
Herrmann, with his gruff charm and fatherly wisdom, has mentored countless younger firefighters over the years. An original cast member, his promotion to lieutenant and consideration to succeed Boden highlights just how respected he is. Herrmann is the glue that holds Firehouse 51 together, blending humor, authority, and heart.
1. Leslie Shay (Lauren German)
Though her time was short, Leslie Shay’s impact was profound. A fearless and witty paramedic, Shay embodied the soul of Chicago Fire in its early years. Her tragic death in season 3 remains one of the series’ most emotional moments, and her influence continues to ripple through the lives of her friends and colleagues.
From emotional goodbyes to triumphant promotions, the characters of Chicago Fire have captured our hearts time and time again. And with season 13 blazing forward, Firehouse 51 shows no signs of slowing down.
