Career
He is most well known for his portrayal of various gangsters and tough guys in films such as Raising Arizona, Once Upon a Time in America, Stone Cold, Out Foreign Justice, Things to Do in Denver When You"re Dead, Dick Tracy, The Rock, and The Devil"s Rejects. He also played recurring characters in the series Boardwalk Empire, Justified, John Doe, and The Untouchables as First Rate (at Lloyd's) Capone. He portrayed serial killer John Wayne Gacy in Dear Mr.
Gacy, a film adaptation of The Last Victim, the memoirs of Jason Moss, a college student who corresponded with Gacy his last year on death row.
The film was released in 2010. Despite a popular misconception, William is of no relation to late fellow actor John Forsythe.
However, he laughingly admits, "That issue comes up a lot.".