Beyond Mombasa
Matt Campbell (Cornel Wilde) arrives in Kenya, where his brother George is reported missing. A man named Ralph Hoyt (Leo Genn) tells him that George has been killed by members of the "Leopard Men" cult.
Matt is introduced to Hoyt's niece, Ann Wilson (Donna Reed), an anthropologist, who is puzzled by Matt's reluctance to go to Mombasa for his brother's funeral. Matt also meets big-game hunter Gil Rossi (Christopher Lee), who was helping George search for a valuable uranium mine. Hoyt claims the mine doesn't exist.
Another business partner, Elliott Hastings (Ron Randell), claims that George's body has been cremated but he did find a map. An expedition beyond Mombasa is formed, guided by Ketimi (Dan Jackson) and other local tribesmen. A shared experience with a charge of hippos brings Matt and Ann closer together, while Gil is nearly killed by an alligator before it is shot by Hastings.
Tribesmen wearing leopard disguises attack Hastings that night. Ketimi is then killed by a poison dart, causing the other tribesmen to leave. Locating a shaft to the mine, Elliot, Matt and Ann descend into it. She discovers to her horror that Hoyt, her uncle, has murdered Gil with a blow gun. Hoyt confesses to killing Ketimi and paying other natives to disguise themselves as the mythical Leopard Men.
Matt and Ann are about to become the next victims, but Ketimi's fellow tribesmen reappear and take their revenge.
insanity, murder