William Forsythe (born June 7, 1955) is an American actor, known for his portrayals of tough-guy, criminal characters.
He appeared in the films Once Upon a Time in America (1984), Raising Arizona (1987), Dick Tracy (1990), American Me (1992), Gotti (1996), The Rock (1996), Blue Streak (1999), Blue Hill Avenue (2001), and The Devil's Rejects (2005). Forsythe was nominated for the Independent Spirit Award for Best Supporting Male for his performance in the film The Waterdance.
On television, he has played the roles of Al Capone on The Untouchables (1993-94), Manny Horvitz on Boardwalk Empire (2011-12), and J. Edgar Hoover on The Man in the High Castle (2018).
Forsythe was born in the New York City borough of Brooklyn, and grew up in its Bedford–Stuyvesant neighborhood. He is of partial Italian descent with Italian (from his maternal grandfather), Scottish, English, Irish and German descent.
He began acting on stage as a teenager, before moving to Los Angeles to pursue a film career, studying at the Beverly Hills Playhouse.
Forsythe started out in minor film roles and guest appearances in TV shows including CHiPs (1977), Hill Street Blues (1981) and T. J. Hooker (1982). He appeared in Once Upon a Time in America (1984), co-starred with John Goodman in Raising Arizona (1987) and as a renegade soldier in Extreme Prejudice.
Forsythe also portrayed comic book villain "Flattop" in Dick Tracy (1990), co-starred with Steven Seagal in Out for Justice (1991) and appeared with former National Football League player Brian Bosworth in the biker action film Stone Cold (1991). He portrayed Al Capone in the short-lived '90s revival of the '60s TV crime show The Untouchables (1993), and also starred in The Waterdance (1992) and the film noir Things to Do in Denver When You're Dead (1995). Forsythe portrayed real-life mobster "Sammy The Bull" Gravano in Gotti (1996)
and supported another ex-NFL player's foray into film acting when L.A. Raider Howie Long debuted in Firestorm (1998).
Forsythe portrayed serial killer John Wayne Gacy in Dear Mr. Gacy, a 2010 film adaptation of The Last Victim, the memoirs of Jason Moss, a college student who corresponded with Gacy during his last year on death row.
Forsythe has three children, including actress Rebecca Forsythe. In 2024, he married Teresa Stevens.