This hostage thriller now gets called film noir, but feels more like gothic melodrama with its woman in peril, deranged male oppressor, old dark house and period setting. It's 1918 and Ida Lupino is a war widow who finds casual work for an itinerant handyman (Robert Ryan) who turns out to be a psychopathic serial killer...
Director Harry Horner was usually a production designer, which is apparent in the increasingly menacing guest house that entraps the vulnerable woman. There's also a touch of expressionism to enhance the atmosphere of threat. And though it starts slowly, the encounter builds to a nerve shredding climax.
Ida Lupino's production company usually focused on thrillers with controversial social themes. Maybe this treats mental illness with more sensitivity than most gaslight melodramas, but its purpose is to create the most intimidating antagonist possible. It's not a case study, but Ryan does build a powerful sense of jeopardy.
The origin as a stage play is evident (also a short story and radio drama- with Frank Sinatra!) but this intensifies the mood of claustrophobic confinement. It's the sort of scenario which became a mainstay of television, but there is a superior imaginative quality here, despite the small budget. And there are better stars.