Who Played Grissom on CSI
William Petersen portrayed Gil Grissom, the lead forensic scientist, on the original CSI: Crime Scene Investigation series. Petersen played the role from the series premiere in 2000 through most of the show's run, establishing the character as one of the most recognizable figures in procedural television. The role defined much of Petersen's career and became a defining part of the CSI franchise.
In the show, Grissom served as the supervisor of the Las Vegas Crime Lab's night shift, guiding a team of investigators through complex forensic cases. Petersen's performance emphasized scientific detail, quiet leadership, and a methodical approach to evidence. The character's calm demeanor and expertise helped shape the tone of the series and influenced the forensic drama genre.
Grissom's Departure and Return
Petersen left CSI: Crime Scene Investigation as a regular cast member after season 12, with his final appearance in 2015. He cited a desire to spend more time with family and pursue other projects, including stage work and film roles. His departure marked the end of the original lead character's central arc on the show.
After leaving the main series, Petersen returned to the CSI universe in a limited capacity. He appeared in the 2015 TV movie CSI: Immortality, which served as a continuation of the original series. The movie brought back several classic characters and allowed Petersen to reprise Grissom in a final storyline for the franchise.
William Petersen's Career Beyond CSI
Before CSI, Petersen built a career in film and theater, with notable roles in movies such as To Live and Die in L.A. and Young Guns II. He also starred in the short-lived series The Beast and later took on roles in projects like the film The Insider, which earned him critical attention for his supporting performance.
After CSI, Petersen continued acting in film and television while also focusing on producing and stage work. He has remained active in the entertainment industry, taking on select roles and maintaining ties to the forensic drama space. For more on his career and recent projects, you can check his profile on IMDb, and for broader industry context, the Television Academy page offers information on his Emmy nominations.