Waldo Brian Donlevy (February 9, 1901 " April 5, 1972), later known as Brian Donlevy was an Irish-born American actor, noted for playing dangerous tough guys from the 1930s to the 1960s. He usually appeared in supporting roles. Among his best-known films are Beau Geste (1939) and The Great McGinty (1940). For his role as Sergeant Markoff in Beau Geste he was nominated for the Academy Award for Best Supporting Actor.
Donlevy starred as US special agent, Steve Mitchell, in 40 episodes of the 1952 TV series "Dangerous Assignment". Mitchell received assignments to exotic locales involving international intrigue from 'The Commissioner' played by Hubert Butterfield.