Sydney Hughes Greenstreet was a British and American actor. While he did not begin his career in films until the age of 61, he had a run of significant motion pictures in a Hollywood career lasting through the 1940s. He is best remembered for the three Warner Bros. films - The Maltese Falcon (1941), Casablanca (1942), and Passage to Marseille (1944) - with both Humphrey Bogart and Peter Lorre. He portrayed Nero Wolfe on radio during 1950 and 1951. He became an American citizen in 1925.

The Maltese Falcon is a 1941 American film noir in which a San Francisco private detective deals with three unscrupulous adventurers, all seeking a jewel-encrusted falcon statuette. Written and directed by John Huston in his directorial debut, the film was based on the 1930 novel The Maltese Falcon by Dashiell Hammett and is a remake of the 1931 film of the same name. It stars Humphrey Bogart as private investigator Sam Spade, Mary Astor as his femme fatale client, and as villains Peter Lorre and Sydney Greenstreet.