He appeared in movies in the United States and Europe, including the Secret Agent 077 trilogy, South Pacific, and a number of Spaghetti Westerns.

Clark's most prominent role in American film came in 1958, when he was cast as Stewpot in South Pacific, an adaptation of the Broadway musical.

[7] In 1959, he made an unsold private investigator TV pilot for a William Campbell Gault-inspired mystery series entitled Brock Callahan,[8] directed by Don Siegel and written by Stirling Silliphant.

In 1971, Clark appeared alongside James Garner in Un Uomo Chiamo Slitta (translated as A Man Called Sledge).

[1] According to fellow actor Robert Woods, Clark died of a heart attack in Rome, Italy on June 1, 2009, three days before his 82nd birthday, shortly after a taping for a program on the mid-1960s Eurospy genre on the TV series Starcult.