After his wife died on the operating table, a disfigured and vengeful doctor, Dr. Phibes, seeks revenge on the medical team. He uses the ten biblical plagues to carry out his gruesome killings, leaving Scotland Yard puzzled. As the body count rises, an inspector and a young doctor race against time to stop Dr. Phibes before he completes his deadly vendetta.

Dr. Phibes, a disfigured doctor, rises from the dead and seeks revenge against those who wronged him. With the help of a mute assistant and various eccentric inventions, he plans to unleash a series of elaborate and gruesome killings. As he continues on his path of revenge, his ultimate goal of immortality becomes clear.