According to Robert Osborne of TCM, this film was at one point intended to be a sequel to Le faucon maltais (1941). Following the success of that film, Warner Bros. wanted to make a sequel. "Falcon" writer/director John Huston said he'd previously written an un-filmed script for Warner Bros. that would be appropriate and would only require the character names to be changed to the Humphrey Bogart, Sydney Greenstreet and Mary Astor characters. However, Warner Bros. discovered they did not own the rights to the characters except for their appearance in "The Maltese Falcon."
Alfred Hitchcock showed early interest in directing; this was after a chance meeting with John Huston in London, years before the film was made, or before Huston had himself become a film-maker.
Eighth of nine films in which Peter Lorre and Sydney Greenstreet appeared together, all released by Warner Bros. from 1941 to 1946, starting with Le faucon maltais (1941).
John Huston was still in the U.S. Army at the time of this production; thus he was unable to direct his own story.