The same year he left CSI, he and his wife of 4 years, actress Monika Casey, got a divorce. William Louis Petersen (born February 21, 1953) is an American actor and producer. He is best known for his role as Gil Grissom in the CBS drama series CSI: Crime Scene Investigation (2000–2015), for which he won a Screen Actors Guild Award and was nominated for a Golden Globe Award; he was further nominated for three Primetime Emmy Awards as a producer of the show. American actor and producer Petersen was part of CSI for nine season before he left. william petersen's reason for leaving csi altogether was to pursue a career in theatre. CSI: CRIME SCENE INVESTIGATION was the long-running CBS police procedural which gained a strong fanbase during its time on screens. Gilbert Arthur "Gil" Grissom is the former night shift supervisor at the Las Vegas Crime Lab. Petersen, who plays Gil Grissom, exited the series in 2009 but came back (along with Marg Helgenberger and Paul Guilfoyle, both of whom had also already left CSI) for this last hurrah. He quit his job to fly out to Costa Rica to reunite with his fiance and former subordinate, Sara Sidle(One To Go). It remains unclear how the show will handle Fishburne's character's exit from the show. The couple has had their ups and downs over the years, so did … Also, why did Dr Langston leave CSI? They subsequently got married. Why did William Petersen really leave CSI as Gil Grissom? However, that doesn't mean the audience has seen the last of Grissom. gil grissoms character left the csi team because he wanted to be with sara sidle. Grissom and Sidle returned to 'CSI' Sunday as the CBS procedural came to an end with the two-hour series finale movie, "Immortality." Petersen To Leave 'CSI' By Rachel July 15, 2008 - 6:07 PM. Click to see full answer. Fishburne, who plays Dr.Langston, joined CSI in its ninth season to fill the void after William Petersen's exit. although it was said he would like to return to csi. The 'CSI' series finale aired Sept. 27 and brought so many of the original cast members back together, including Grissom and Sara. Crime procedural CSI: Crime Scene Investigation debuted on CBS in 2000 and follows the titular team of investigators who used science to solve murders or other crimes. Gil Grissom is saying goodbye. CSI: Why did Jorja Fox really leave CSI as Sara Sidle? The show's use of science and its likable cast of characters - including William Petersen's Gil Grissom and … According to Ausiello, the tenth episode of CSI: Crime Scene Investigation's ninth season will be the last appearance of William Petersen (Gil Grissom) as a full-time series regular on the series. George is now 52 and a father to one daughter. Fishburne decided against renewing his deal with CSI after re-upping for only one season last year. He stayed on the show for a whopping 15 years, until leaving right before the finale to pursue his next TV role as Jack Dalton in MacGyver, a role he played until 2019. The original series starred William Petersen as a CSI senior supervisor working for the Las Vegas Police Department and along with his colleagues took on various cases. Here's why Gary Dourdan's fan-favorite Warrick Brown exited CSI: Crime Scene Investigation during season 9.