William Forsythe is an American actor best known for playing "tough guy" roles in movies such as Dick Tracy, American Me, The Rock and Dear Mr. Gacy.
He also starred as Constantine Alexander, an old school leader of the Mob and Grace's father-figure/protector, in the medical crime drama television series The Mob Doctor, from 2012-2013.
Forsythe started his career with a couple of smaller film roles and guest appearances in highly-rated TV shows such as CHiPs, Hill Street Blues and T.J. Hooker.
He quickly moved into feature films, including playing a small-time hoodlum in Once Upon a Time in America; a hilariously funny performance as a bumbling jail escapee alongside John Goodman in Raising Arizona; and a renegade soldier in Extreme Prejudice.
Versatile and entertaining, Forsythe portrayed comic book villain Flattop in Dick Tracy, tangled with vengeful cop Steven Seagal in the hyper-violent Out for Justice and locked horns with ex-NFL linebacker Brian Bosworth in the biker action film Stone Cold.
He was perfectly cast as prohibition mobster Al Capone in the short-lived '90s revival of the classic '60s crime show, The Untouchables.
He continued to play edgy, nefarious individuals in the thought-provoking The Waterdance; the oily film noir piece, Things to Do in Denver When You're Dead; as real-life mobster Sammy 'The Bull' Gravano in the made-for-TV movie Gotti; and he supported another ex-NFL player's foray into film acting when Los Angeles Raider Howie Long debuted alongside Forsythe in Firestorm.
Forsythe has remained busy with a plethora of feature films, telefilms and TV series appearances. He developed a cult following amongst film fans for his attention-grabbing roles in City by the Sea, The Devil's Rejects and Rob Zombie's Halloween.
Forsythe also portrayed notorious serial killer John Wayne Gacy in Dear Mr. Gacy and gained critical acclaim for playing real-life Jewish butcher Manny Horowitz in Boardwalk Empire.
Forsythe also reprised the role of Jake LaMotta in Raging Bull II.
He currently splits his time between Chicago and Los Angeles.