Tab Holland, newspaper reporter and a friend of a local police investigator, is surprised to discover that his roommate’s uncle Jesse Transmere, a wealthy miser, has been found murdered in a cellar vault locked from the inside. More surprising is the fact that Ursula Ardfern, a famous actress and new acquaintance of Tab’s, has had her plays backed by the murder victim in the past.

Although he has been regularly reporting on the case for the newspaper, Tab’s interest in the case intensifies after both his own apartment and the murdered man’s house are ransacked.

Although it’s yet another entry in Edgar Wallace’s locked-room mysteries, The Clue of the New Pin also explores the claim of various religions in having exclusive access to the truth, or the only path to spirituality.