Peter Krause, who played Bobby Nash, the captain of LAFD’s Station 118, has left the series after eight seasons. His character met a tragic end in Season 8, Episode 15, “Lab Rats,” while giving his only available vial of a life-saving vaccine to teammate Chimney.
The decision to kill off Nash was not Peter Krause’s choice but rather a creative one made by the show’s team, according to showrunner Tim Minear. Minear explained that Bobby’s death makes sense in the context of his character arc and would have a significant impact on every single character’s story.
Krause himself praised Minear’s bold decision, saying it was an honor to play Nash and that his character was built for sacrifice. He also expressed gratitude towards his 9-1-1 family, including the crew, writers, directors, and guest cast.
Nash’s death took place during a lab explosion, where he revealed he had kept his infection a secret to protect his team. His final moments were portrayed in an emotional scene, as he shared a goodbye with Buck and Athena before the virus took his life.
Minear had to pitch Bobby’s death scene to “the highest levels” of the network before it was officially approved. He aims to make the character’s death feel real and alive by having every single episode focus on the aftermath for the next three episodes.
The show will continue with Athena taking center stage, and Minear has intentionally avoided discussing what comes next in the storyline.
Source: https://www.forbes.com/sites/monicamercuri/2025/04/18/why-is-peter-krause-leaving-9-1-1-the-reason-behind-his-shocking-exit-as-bobby-nash