Dr. Anton Phibes, a famous concert organist with doctorates in both music and theology, is believed to have been killed in a car crash in Switzerland in 1921, while racing home upon hearing of the death of his beloved wife, Victoria, during surgery. Phibes survived the crash, but was horribly scarred and left unable to speak. He remade his face with prosthetics and used his knowledge of acoustics to regain his voice. Resurfacing secretly in London in 1925, Phibes believes his wife was a victim of her doctors’ incompetence, and begins elaborate plans to kill those he believes are guilty for her death.^[7]

Aided in his quest for vengeance by his beautiful and silent assistant Vulnavia, Phibes uses the Ten Plagues of Egypt as his inspiration, wearing an amulet with Hebrew letters corresponding with each plague as he conducts the murders. After three doctors have been killed, Inspector Trout, a detective from Scotland Yard, learns that they all had worked under the direction of Dr Vesalius, who tells him the deceased had been on his team when treating Victoria, as were four other doctors and one nurse. Trout discovers one of Phibes’ amulets (torn off during a struggle) at the murder scene of the fourth doctor, which takes place while he is interviewing Vesalius. He first takes it to the jeweller who made it, then to a rabbi to learn its meaning. Now believing Phibes may still be alive, Trout and Vesalius go to the Phibes mausoleum at Highgate Cemetery. Inside they find a box of ashes in Phibes’s coffin, but Trout deduces they are probably the remains of Phibes’s chauffeur. Victoria’s coffin is empty.

The police are unable to prevent Phibes from killing the remaining members of Vesalius’s team, so they focus their efforts entirely on protecting Vesalius himself. Phibes kidnaps Vesalius’s son Lem, then calls Vesalius and tells him to come alone to his mansion on Maldene Square if he wants to save his son’s life. Trout refuses to let him go so Vesalius knocks the inspector unconscious, then races to Phibes’s mansion, where he confronts him. Phibes tells him his son is under anaesthesia and prepared for surgery. Phibes has implanted a key near the boy’s heart that will unlock his restraints. Vesalius has to surgically remove the key within six minutes (the same time Victoria was on the operating table) to release his son before acid from a container above Lem’s head is released and kills him. Vesalius succeeds and moves the table out of the way. Vulnavia, who was ordered to destroy Phibes’s mechanical creations, is surprised by Trout and his assistant; backing away, she is drenched with the acid and killed.

Convinced that he has accomplished his vendetta, Phibes retreats to the basement to inter himself in a stone sarcophagus containing the embalmed body of his wife. He proceeds to drain his blood while simultaneously replacing it with embalming fluid and lies down in the sarcophagus next to Victoria. The coffin’s inlaid stone lid lowers into place, concealing it. Trout and the police arrive but cannot find Phibes. They recall that the “final curse” was darkness just before the basement goes dark.