Guide Note

William Petersen is an American producer, television, stage and film actor hailing from Evanston, Illinois. Petersen can currently be seen on the hit CBS television series CSI. Petersen has been a part of the cast since the first episode of the show. Rumors have been circulating for a few years that he will be leaving but not official confirmation has come as of yet.

Petersen's other acting credits including Young Guns II, Manhunter, Fear, The Rat Pack, The Skulls, The Contender and Without a Trace.

Petersen's producing credits include CSI, Keep the Change and Hard Promises.

Fast Facts

1. Full Name: William Louis Petersen
2. Also Goes By: Billy Petersen
3. Born: February 21, 1953
4. Birthplace: Evanston, Illinois
5. Years Active: 1981 - Present
6. Portrays Gil Grissom on CSI
7. Married his first wife in 1974
8. Divorced in 1981
9. Married current wife Gina Cirone in 2003
10. Daughter, Maite, from first marriage
11. Has one grandson, Mazrik William
12. Fan of the Chicago Cubs

1. "I'm not even sure that Grissom realized that he was saying it or that at the moment, he didn't realize that everybody was hearing it. It was a revelation on his part. And again more importantly that's really what has come to pass on this season is the realization on Grissom's part that...he loves someone." — William Petersen on Grissom and Sara's relationship
2. "The best way to put this is that, you know, i'm not a huge fan of cliffhangers endings. However I think because of what we've done with the whole minituare killer story line that in a way we've earned this ending, you know? It's not something that you can just wrap up quickly and walk away from it." — William Petersen on the season seven finale
3. "She's sort of the-the quintessential anthropological study for Grissom. You know she's-she's just so fascinating to him because she's so...out there." — William Petersen on Lady Heather
4. "Two years from now, there'll be another one in Philadelphia and one in Toledo. If it works, they're going to use it until it doesn't work anymore. You can't tell them the golden egg is going to get broken." — William Petersen on CSI spin-offs