Because it was released by the premier horror studio Universal, focuses on an old castle with a spooky room, and features horror star Lionel Atwill, SECRET OF THE BLUE ROOM has been marketed as a horror film throughout the year. It's actually a whodunit with horror elements that influence but never dominate the film. But it would be close-minded to reject this film just because it's not a full-fledged chiller. SECRET OF THE BLUE ROOM is an enjoyable film that projects an air of menacing mystery and efficiently moves the plot with a palpable suspense until the movie's resolution.<br /><br />SECRET OF THE BLUE ROOM benefits from attractive sets (leftover from THE OLD DARK HOUSE and FRANKENSTEIN) that convey an ornate yet forbidding castle milieu. Director Kurt Neumann, while no stylist in the James Whale vein, effectively utilizes the setting's atmospheric potential. He provides a suitably eerie aura with taste and restraint, avoiding obvious stunts like self-playing pianos. Such gimmicks would damage the film's mood and credibility.<br /><br />On the whole, performances are good. The actors and actresses provide believable characterizations that help propel the plot. Particularly impressive are Lionel Atwill as the castle owner troubled by his estate's secrets and Edward Arnold as a detective who handles the castle's mysteries in a domineering, no-nonsense manner. Elizabeth Patterson is mildly annoying as a terrified maid, but fortunately her performance doesn't affect BLUE ROOM's atmosphere.<br /><br />Curiously, a few of the plot's riddles remain unexplained at the film's end. It would have been logical for Universal to provide a sequel with the same fine cast in order to resolve everything. Instead, the studio chose to remake the film twice with different performers. But BLUE ROOM's minor plot holes shouldn't detract one from enjoying this well-made mystery.