A woman thinks her daughter is out to kill her, and hires a detective agency to help her. "Devil's Mask" had a perfectly respectable cast, and a good solid script. With shrunken heads from south America, a panther, and even the use of hypnosis were all probably pretty new and exotic in 1946. (Although, when they try to put someone under hypnosis, they shine a bright light in the actor's eyes, and loudly tap a pencil over and over, so not sure how deeply the actor could have gone under....) The acting by some of the actors is a tad flat, and assistant detective Doc Long (Bart Yarborough) spouts more southern descriptive phrases than necessary, probably the reasons for the low rating on IMDb and membership in the "B Movie" club. The lead detective playing Jack Packard , Jim Bannon, had played detectives and cowboys, and was married to Bea Benaderet (Pearl Bodine, in the Beverly Hillbillies). Another interesting connection, Frank Wilcox, who plays Professor Logan, would also go on to be the oil company president on "Beverly Hillbillies". Also.... Mona Barrie and Bea Benaderet were both in "The First Time". Anita Louise, who plays the daughter Janet in Devil's Mask, was really only six years younger than the Mother Mitchell (Mona Barrie). good Whodunnit. no big glaring plot holes. no big car chase scenes.