Dick Powell, who is best known as a crooner and romantic lead in musicals like 42nd Street (1933), is miscast as Philip Marlowe in what is otherwise a stylish adaptation of Raymond Chandler's Farewell, My Lovely (the title of the 1975 remake with Robert Mitchum carrying the mantle). That aside, the film is classic noir with John Paxton's script preserving Chandler’s sardonic dialogue and Harry J. Wild's photography creating the noir atmosphere with style.
Marlowe tells the story in flashback of how he was hired by ex-con, Moose Malloy (Mike Mazurki) to find his missing girlfriend, Velma. One thing leads to another, in particular, the beautiful Mrs Helen Grayle (Claire Trevor) and a stolen necklace. The lies and the bodies duly pile up as Marlowe follows the trail, and, as is typical with the genre, greed and a false heart are at the bitter end of the line. Although Mitchum did world-weary better than Powell, this remains the definitive version.
FYI: There is also a 1942 version, The Falcon Takes Over (unseen), with George Sanders in the lead.