A burly, commanding actor known almost as much for the tumultuous quality of his offscreen life as that of his onscreen roles, Tom Sizemore has carved out a niche for himself in such guys 'n' guns films as Natural Born Killers, Strange Days, Heat, and Saving Private Ryan.

Born in Detroit, Sizemore was educated at Wayne State and Temple University, earning a Master's in theater at the latter. He enjoyed an auspicious debut year in 1989 when he appeared in no less than four movies including Oliver Stone's Born on the Fourth of July. That same year, the actor won the semi-regular role of Vinnie Ventressa on the popular TV drama China Beach. He went on to do starring work in such films as Stone's Natural Born Killers (1994), Carl Franklin's highly praised crime noir Devil in a Blue Dress (1994) and Michael Mann's crime thriller Heat. Sizemore's involvement with the latter film marked a personal turning point for him; for years he suffered from a well-publicized addiction to heroin, and he seemed to be losing his battle until he met his Heat co-star and childhood icon Robert De Niro, who, Sizemore subsequently admitted in interviews, convinced him to go into rehab.

In 1998, Sizemore starred in what was possibly his most high-profile role to date in Steven Spielberg's WWII epic Saving Private Ryan. Cast as Sgt. Horvath, Tom Hanks' right hand man, the actor earned positive notices as part of a stellar ensemble cast that also included Giovanni Ribisi, Matt Damon, Jeremy Davies, and Vin Diesel. He subsequently porked out to play mob boss John Gotti in the made-for-TV Witness to the Mob and then returned to the screen in Martin Scorsese's Bringing Out the Dead (1999), which cast him as Nicolas Cage's ex-best friend. In 2000, Sizemore starred alongside Val Kilmer and Carrie-Anne Moss in the sci-fi adventure Red Planet; that same year, he appeared in Play It to the Bone, a boxing drama starring Woody Harrelson and Antonio Banderas. With the release of Pearl Harbor and Black Hawk Down the following year, the grizzled screen veteran seemed as if he may be threatening to becoming something of a later-day action star.

Though to this point Sizemore's work in features had left him with little experience in the realm of television, all of that would change when he took the lead in the 2002 series Robbery Homicide Division. For an actor who excelled at playing hardened detectives and rough cops, the show seemed the ideal star vehicle for Sizemore, and after contributing vocal work for the controversial video game Grand Theft Auto: Vice City that same year, he stepped into the lead for the crime thriller Swindle as the year wound to a close. A supporting role in Dreamcatcher got 2003 off to a shaky start, and things only went downhill from there when, in October of that year, the troubled actor entered rehab before being sentenced to six months in prison on domestic violence charges. Though his personal life may have been somewhat in flux, one certainly couldn't tell by looking at his screen credits for 2004 -- a year in which Sizemore would appear in no less than four films including the family adventure Fly Boys.