Gaslight (1940)
This could have been a stodgy adaptation of a British play about a man who is driving his wife insane to cover up his criminal past. The film is saved by Antom Walbrook, who plays the husband. He gives a controlled performance--at first he seems annoying, but gradually he brings out his character's sinister nature. His character is one of the most despicable I have seen in a long time. As the film progressed I felt more and more tense, and could only get relief when the film ended. Diana Wynyard is also good as the meek and passive woman who is victimized by her husband, although I wish there was more to this character (I suppose she was playing to Victorian ideals of feminity).