Dr. Jekyll And Mr. Hyde (1941)

Dr. Jekyll (Spencer Tracy) is doing research and experimentation on the duality of man's nature, his good and his evil inhabiting the same soul. To this end, he invents a serum to facilitate this change. He names his evil side Mr. Hyde. But soon his experiment goes out of control and he no longer can contain it. Based on the book by Robert Louis Stevenson and directed by Victor Fleming (GONE WITH THE WIND). There have been countless versions of Stevenson's novella on stage, film and TV. I like this version best. MGM during its "golden age" wasn't much on horror films (that was Universal's domain). This has the usual lush MGM trappings but it remains an intense descent into horror. Unlike Fredric March in 1932 version, Tracy doesn't overdo the make up and depends on his acting to transition into Mr. Hyde and shows us what a sadistic brute can be. But the acting honors go to Ingrid Bergman who is superb as the cockney barmaid who has the misfortune to encounter Mr. Hyde and becomes his abused (both psychologically and physically) mistress. Your heart breaks for her, trapped and unable to escape his clutches. There's a wonderful score by Franz Waxman. With Lana Turner as Jekyll's peaches and cream fiancee, Donald Crisp, Ian Hunter, C. Aubrey Smith, Sara Allgood, Barton MacLane and Frances Robinson.