Slade, a serial killer, is a lodger in a 19th-century family's London home. So is a singer, Kitty Langley, who definitely has caught Slade's eye.
Women are being brutally killed in the Whitechapel district. Scotland Yard is investigating and a detective, John Warwick, begins to cast his suspicions in Slade's direction. Kitty, meanwhile, has also developed an attraction to Slade.
Slade goes to see her perform at a cabaret. He goes backstage afterward and tries to make her his next victim, but Warwick's men get there just in time. Unwilling to be taken into police custody, Slade flees to the riverbank and leaps to his death.
Merle Oberon as Kitty Langley (singing voice was dubbed by Lorraine Elliott)
The New York Times gave the film a positive review, "If The Lodger was designed to chill the spine—as indeed it must have been, considering all the mayhem Mr. Cregar is called upon to commit as the mysterious, psychopathic pathologist of the title—then something is wrong with the picture. But, if it was intended as a sly travesty on the melodramatic technique of ponderously piling suspicion upon suspicion (and wrapping the whole in a cloak of brooding photographic effects), then The Lodger is eminently successful." Variety wrote, "With a pat cast, keen direction and tight scripting, 20th-Fox has an absorbing and, at times, spine-tingling drama". TV Guide rated it 4/5 stars and wrote, "Cregar is absolutely chilling in this Jack the Ripper tale, perhaps the best film made about Bloody Jack."