Clark was born Bernard Zanville in Brooklyn, New York, the son of Jewish immigrants, Samuel, a sporting goods store owner, and his wife, Rose. The date of birth is a matter of dispute, amongst different sources. He graduated from Cornell University and earned a law degree at St. John’s University School of Law in Queens, New York. During the Great Depression, he worked as a boxer, baseball player, construction worker, and model. Modeling brought him in contact with people in the arts. He gradually perceived them to be snobbish, with their talk of the “theatah”, and “I decided to give it a try myself, just to show them anyone could do it.” He progressed from small Broadway parts to larger ones, eventually taking over the role of George from Wallace Ford in the 1937 production of Of Mice and Men.[1] Clark got his big break when he was signed by Warner Bros. in 1943. He worked alongside some of his era’s biggest stars, often in war movies such as Action in the North Atlantic (1943), his breakthrough part, opposite Humphrey Bogart, Destination Tokyo (1943) with Cary Grant, and Pride of the Marines (1945) with friend and fellow New Yorker John Garfield. According to Clark, Bogart gave him his stage name. He also played a surly artist opposite Bette Davis in A Stolen Life.

Exhibitors voted Clark the 16th most popular star at the US box office in 1945, and during the 1950s, he became one of a small group of actors (excluding the original ‘founding’ members brought in at the Studio’s inception) awarded life membership in The Actors Studio. Clark played Peter Chambers in the short-lived radio show Crime and Peter Chambers, a half-hour show that aired from April 6 to September 7, 1954. Clark first appeared on television in the late 1940s, and after the mid-1950s worked much more in that medium than in feature films. In the 1954-1955 season, he co-starred as the character Richard Adams, with Gary Merrill in the role of Jason Tyler, in the NBC crime drama Justice, about attorneys of the Legal Aid Society of New York. In 1959, he reprised Humphrey Bogart’s role as Slate in Bold Venture, a short-lived television series. He also guest starred on a number of television shows, including Faye Emerson’s Wonderful Town, Appointment with Adventure, CBS’s Rawhide in the episode “Incident of the Night Visitor”, and The Twilight Zone, in the episode “The Prime Mover”. In 1970, he guest-starred in an episode of The Silent Force. He also played Lieutenant Tragg in the short-lived revival of the Perry Mason television series in 1973, and appeared in the 1976 miniseries Once an Eagle.