The Devil Commands is a 1941 American horror film directed by Edward Dmytryk and starring Boris Karloff. The story was adapted from the novel The Edge of Running Water by William Sloane.
Dr. Julian Blair is engaged in unconventional research on human brain waves when his wife is tragically killed in a freak auto accident. The grief-stricken scientist becomes obsessed with redirecting his work into making contact with the dead and is not deterred by dire warnings from his daughter, his research assistant, or his colleagues that he is delving into forbidden areas of knowledge. He moves his laboratory to an isolated New England mansion where he continues to try to reach out to his dead wife. He is aided by his mentally-challenged servant Karl and abetted by the obsessive Blanche Walters, a phony medium, who seems to exert a sinister influence over him. When their overly curious housekeeper discovers the truth about their experiments, her death brings the local sheriff in to investigate.
Tropes:
- Creepy Housekeeper: Once she understands both what Blair is trying to do and that he might actually be capable of succeeding, Mrs. Walters begins looking ahead to the wealth and power that such success could bestow upon anyone wily enough and ruthless enough to exploit it properly. Blair, in contrast, remains monomaniacally fixated upon talking to his wife, and the combination of that blinkered vision and the doctor’s native guilelessness gives Walters an opening to become the senior partner in their project. She’s the one who finds the remote New England mansion to which the pair retreat to carry on their work in isolation and secrecy. She’s the one who manages all the household affairs, engaging the scrupulously incurious Mrs. Marcy as housekeeper, interposing herself between Blair and any of the locals who might wish to see him, and intercepting all the mail either leaving or entering the house so as to prevent any communication between the doctor and his former associates— including and especially is daughter Anne.
- Grave Robbing: Dr. Blair has been conducting experiments to communicate telepathically with the dead, and to expedite this he has been robbing a few graves here and there.
- The Igor: Dr. Blair is aided in forbidden experiments by his mentally-challenged servant Karl, who was rendered mute by one of Blair's experiments.
- I Never Got Any Letters: When Anne finally gets to see her father after years of separation, she demands to know why he never replied to her letters, he says he never received any. When she insists she sent them, Dr. Blair says Mrs. Walters always collects the mail from the post office and starts to realise that Mrs. Walters has been deliberately keeping him isolated and manipulating him for years.
- The Lost Lenore: Dr. Julian Blair is engaged in unconventional research on human brain waves when his wife Helen is tragically killed in a freak auto accident. The grief-stricken scientist becomes obsessed with redirecting his work into making contact with the dead. He moves his laboratory to an isolated New England mansion where he continues to try to reach out to his dead wife.
- Make It Look Like an Accident: Sheriff Ed Willis eventually succeeds in suborning Mrs. Marcy to act as his spy, but the maid’s snooping gets her killed when she finds what the sheriff is looking for. Blanche is able to engineer a plausible-looking accident to account for the woman’s death by making it look like she she had fallen off the clifftop path while walking home in the dark, but Mr. Marcy is not persuaded by her ruse.
- Offscreen Afterlife: None of Dr. Blair's attempts to communicate with his dead wife gain him any knowledge about the afterlife, and his final experiment collapses the roof of his lab on top of him.
- Phone Call from the Dead: One night following his wife's death, Blair absentmindedly switches on the power to his brainwave-recording equipment, only to turn it off again during one of his more lucid moments. Then Blair finds his attention drawn to the graph, which ought to bear nothing but a flat trace for the minute or two that the machine was turned on, given that the receiver wasn’t hooked up to anyone or anything. That’s not what he sees, though. Not only is there a wave pattern on the graph, but it’s Helen’s wave pattern! Blair’s research has already shown that only Helen’s brain could produce that pattern, so it’s difficult to find any explanation for the graph save that the idle recorder was somehow picking up Helen’s thoughts from beyond the grave.
- Phony Psychic: Karl takes Dr. Blair to see the medium Blanche Walters, whom Karl believes allows him to talk to dead mother's spirit. Blair easily finds and exposes the hidden speakers and projectors whereby Walters fakes her spirit manifestations.
- Shoot Out the Lock: Sheriff Willis shoots the lock off the gate at Dr. Blair's remote New England mansion when he arrives there with Richard and Anne.
- The Speechless: Dr. Blair's mentally-challenged servant Karl suffered brain damage and lost the ability to speak during an accident while Dr. Blair was recording his brainwaves.
- Strapped to an Operating Table: When Dr. Blair decides that his daughter Anne is conduit he needs to be able communicate with her dead mother Helen, he straps her into a chair that looks a lot like an electric chair and affixes the brainwave helmet to her head.
- These Are Things Man Was Not Meant to Know: The other scientists regard Dr. Blair's attempts to communicate with the dead as this. His fellow scientists don’t mock him, being too respectful of his previous brain wave research, but they argue that to use science to bridge the gap between life and death is irresponsible: “We don’t know what evil may be lurking beyond that veil,” one declares. The dread here is less about death than about opening a telecommunications bridge to the afterlife, and what wickedness might seep through.
- Torches and Pitchforks: After the death of his wife, Seth Marcy whips up the locals into a frenzy and they storm Dr. Blair's mansion just as he is conducting his final experiment.
