Here’s the WTF? of the day … fans of CSI: will be very bummed (and most probably as shocked as I am) to learn that Entertainment Weekly is reporting that William Petersen, the actor who plays lead CSI Gil Grissom, has decided to “say goodbye” to the show and step down as the main man on the show. Petersen is reportedly staying on as an executive producer on the show and will reprise the role of Gil Grissom “whenever CBS asks” but after this season’s 10th ep, he will no longer be a regular castmember on the show:

CSI executive producer Carol Mendelsohn has confirmed exclusively to Entertainment Weekly’s Michael Ausiello that William Petersen (Gil Grissom) will be gone by midseason! And not “off too do a play” gone like he was back in 2006. No, this season’s 10th episode will be his last as a full-time series regular. “Billy is leaving,” confirms the show’s executive producer, Carol Mendelsohn. “But he will remain throughout the run of the series an executive producer. And he will, whenever CBS asks, come back. I don’t think you’ve seen the last of Gil Grissom.” Neither does Petersen. In fact, in an exclusive interview conducted last Friday, the eight-year CSI vet seemed almost reluctant to characterize his departure as, um, a departure. Citing both his ongoing role as an executive producer AND his intention to return on occasion as a (very special) guest star, he said, “I’m in a great place in terms of knowing that I’ll be more free to make choices. And I’m responsible enough to not do it in a way that would hurt [the show]. I want it to work for the writers, I want it to work for the cast, and, MOST importantly, I want it to work for the audience,” he added. “I don’t want them to abandon the show.” In the meantime, Mendelsohn is plotting one hell of a send-off for her leading man. The events of last season’s finale — specifically the death of Gary Dourdan’s Warrick — will push Grissom to the breaking point. “The easiest way to describe Grissom is ‘in crisis,’” Petersen told me. “As a man. As a scientist. As a teacher. As a middle-aged person who has been very successful at what he’s done… [he] wonders, ‘What’s the point?” Helping Grissom through the crisis will be his true love, Sara, played by Jorja Fox, who is returning for multiple episodes, starting with the season premiere. “I wouldn’t want to say exactly what we’re going do — I want people to watch, certainly,” he chuckled. “But Sara is involved… It’s often darkest just before the dawn.” And lest anyone read any hidden meaning into that statement, the actor reiterated, “For me, it’s a really good situation. I don’t want the audience to think it’s NOT… [It isn't] like there’s something going on, like ‘Petersen’s unhappy,’ ’cause it’s not true. It’s quite the contrary” … Executive producer Carol Mendelsohn also says that her team was anything but blindsided by the upcoming departure of William Petersen. “We do have a plan,” she says … “We’re not saying whether or not Warrick lives or dies,” hedges Mendelsohn, “but we WILL say the the premiere may be the last time our loyal fans see the entire original CSI cast together.”

Wow! This is a huge shocking change to an already very solid, very popular TV series. I was really bummed when Jorja Fox (Sara Sidle) left the show last season (but am relieved that she is coming back for “multiple episodes”) and was surprised that they decided to kill off Gary Dourdan’s character (Warrick Brown) in the season finale (no matter what they won’t say, Warwick got Peaced the Spork Out) but this Peterson leaving CSI: thing is madness. He is the crux of the show … I can’t imagine any other character stepping in to take Gil Grissolm’s place. This is a risky move … I hope it plays out well. I love this show and would hate to have it turn to garbage by replacing half the cast with new folks who may possibly ruin the show. Thankfully hottie George Eads (Nick Stokes) is still on the show … if he leaves, I’m out.

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