"Oh, there's no such thing as sanity. At it's best a heroic and precarious little hiding place in which we try to conceal ourselves from the devils...The devils of time, space, things unknown, and the past."
Although its title suggests conventional horror, "The Mad Doctor" is a pitch black thriller with some with some truly harrowing subject matter. Basil Rathbone plays Dr. Sebastien, a Bluebeard-like psychiatrist who recently killed off his wealthy wife Ida. After arousing the suspicion of local doctor Ralph Morgan, Rathbone leaves town. He soon finds his next mark, a deeply troubled young socialite named Linda that's been suffering with suicidal ideations.
Rathbone is accompanied in his efforts by Martin Kosleck as Maurice, a sort of male secretary. After seeing these two interact, it becomes very clear that they are more than criminal accomplices. When we see Kosleck in Rathbone's home or office, he's variously arranging flowers, spritzing himself with cologne, fussing with Rathbone over a choice of tie, and languorously sketching a black cat while wearing a bathrobe. When Rathbone starts to become genuinely interested in Linda, Kosleck responds with wounded jealousy.
This is very obviously a coded gay relationship, years ahead of the one in Hitchcock's "Rope." The scenes between Rathbone and Kosleck, both superb actors, positively crackle. In one scene, Rathbone gives a bone chilling monologue describing his contempt for dead wife Ida: "These atrocious paintings. This absurd wallpaper. These pathetic antiques. They all breathe her spirit. I can almost see her now coming down those stairs with that foolish smile and the love light in her eyes. I can never forgive her the eight months spent in this cave of romance."
The danger and intensity only ratchet up from there, climaxing in a truly haunting and beautifully executed ending. This is one of Basil Rathbone's most underrated films.
