What Happened To Beloved CSI Star William Petersen?

William Petersen had been acting in Hollywood for over 15 years before locking into the role that would truly make him a household name with his turn on "CSI: Crime Scene Investigation." The celebrated actor got his big break with a starring role in director William Friedkin's 1985 neo-noir crime drama "To Live And Die In L.A.," which he followed a year later starring as detective and criminal profiler Will Graham in Michael Mann's iconic "Manhunter." It wasn't until 2000 that he introduced the world to crime scene analyst and investigator Gil Grissom in the CBS series "CSI" and changed his career forever.

To say "CSI" was a megahit and TV phenomenon would actually be an understatement. The series spawned three spin-off series (a couple of which even featured Meghan Markle in guest roles), a video game, a board game, and ran for an astounding 15 seasons. Petersen exited as a series regular after nine seasons, but returned for intermittent guest appearances and starred in all 10 episodes of the first season of the revival series, "CSI: Vegas" in 2021. The role is what truly made Petersen a superstar, and it seems fitting that his final role would be playing Gil Grissom for one last crime-solving adventure.

However, his last job on TV proved to be so physically demanding that he wound up needing to be hospitalized. Petersen was admitted to the hospital amid filming "CSI: Vegas" in August 2021. A rep for the actor told People at the time that he was "exhausted from long hours on set for the past 12 weeks and was taken to the hospital as a precautionary measure." After Petersen finished filming, the actor decided to officially retire from acting altogether and moved his family out to Chicago, not far from his hometown of Evanston, Illinois.

Petersen was spotted by paparazzi for the first time in several years in June 2026, when he was photographed out and about in Los Angeles. The photos, first published by the Daily Mail, showed the 72-year-old Petersen looking casual and comfy in a pair of dark jeans, a black, short-sleeved button-down shirt, and a gray visor. The appearance came just a few months after Petersen dished on his decision to permanently step back from Hollywood and enjoy life with his wife, Gina Cirone, and their twins, a son and a daughter, who were born in August 2011.

"I don't really want to do anything!" Petersen told People at a 40th anniversary celebration screening of "To Live And Die In L.A." in November 2025. "I've done 40 plays or whatever, I've done movies, I've done television. I managed to participate in all three mediums, in terms of what you can do as an actor."

According to Petersen, he never expected to have the career he managed to enjoy in the first place. The celebrated actor told the outlet that he "had no intention of living in Los Angeles, ever, or being in the movies or having a television show." All of his success was a fortunate result of simply trying to be good at what he loved to do, and he was just "incredibly lucky" to forge the path he managed to take. However, after years of doing the job, Petersen said he simply doesn't have the same kind of drive for the spotlight, explaining, "I just don't have the ego to go get in front of cameras anymore."