In Invisible Ghost, Lugosi plays Charles Kessler, a wealthy physician who recently lost his wife to another man. Sadly, Kessler’s wife was involved in a car accident that supposedly led to her death. Kessler lives in a large house with his daughter Virginia (played by Polly Ann Young), who is being courted by Ralph Dickson (John McGuire).

Unbeknownst to the family, Mrs. Kessler (Betty Compson) survived. However, she suffers from amnesia, and it is because of this that the family gardener Jules Mason (Ernie Adama) elects to hide her in the home’s basement.

But Mrs. Kessler has grown malevolent, possibly because of the brain damage caused by the car accident. Having somehow acquired the power of overwhelming hypnotism, she forces her husband to commit several grisly murders in the family home. Kessler is unaware of his deeds and does everything he can solve the mystery, even hosting detectives at his home. Instead, the cops pin the murders on Dickson, who is sent to the electric chair. In a sequence later made famous by Barbara Steele, actor John McGuire returns, explaining that he is Ralph’s twin brother, Paul.