Dana Andrews is investigating a devil cult in England, with the help of Peggy Cummins in this film, called Curse of the Demon in the US. Directed by Jacques Tourneur.
There's an interesting link to film noir with this film. Andrews did, among others, Laura, Cummins was memorable in Gun Crazy and of course Tourneur did Out of the Past. The film looks great, and has some creepy scenes - it's mostly psychological horror, based on mood and atmosphere, in the style of Tourneur's previous films like Cat People. There's a special effect involving smoke that is pretty impressive. Unfortunately the producer wanted to show the demon of the title, and well, he shouldn't have. It's obviously some rubber thing that completely breaks the tension. The film, or possibly the short story it was based on, might be an inspiration for Sam Raimi's Drag Me To Hell. The ending is similar, where the person who is cursed is trying to give the curse back.