Gallagher was the first person on The O.C. to be cast. Despite being portrayed as Jewish on the show, Gallagher is of Irish Catholic descent. He now hosts an annual award ceremony named "The Sandy Cohen Awards," or The Sandys, which in honor of his character now give a scholarship to a law school student at UC Berkeley who wants to become a public defender.
Gallagher first becoming famous for his role in Steven Soderbergh's Sex, Lies, and Videotape (1989). He is a graduate of Tufts University and a member of the Tufts Beelzebubs.
Gallagher also specializes in character parts of varying degrees both good or bad guys. He played a potential career threat to Tim Robbins studio executive in The Player as a possible replacement; the coma-induced "fiancé" of Sandra Bullock in While You Were Sleeping; an egotistical real estate salesman having an affair with Annette Bening in American Beauty; and a villainous media executive in Mr. Deeds, in one of the film's more inspired moments when a game of tennis turns into a full tennis ball assault on his head.
Gallagher also released an album entitled "7 Days in Memphis" in 2005, on the Sony BMG label. This includes a studio recording of his performance of "Don't Give Up On Me" (originally by Solomon Burke), which featured in an episode of The O.C..
- How to Deal (2003)
- Mr. Deeds (2002)
- Center Stage (2000)
- American Beauty (1999)
- The Man Who Knew Too Little (1997)
- To Gillian on her 37th Birthday (1996)
- Titanic (TV) (1996)
- While You Were Sleeping (1995)
- The Hudsucker Proxy (1994)
- The Player (1992)
- Sex, Lies, and Videotape (1989)
- High Spirits (1988)
- Long Day's Journey Into Night (1987)
- Dreamchild (1985)
- Summer Lovers (1982)
- The Idolmaker (1980)