In ancient Persia, an evil creature called the Djinn wreaks havoc on a local kingdom before being sealed inside a stone – a fire opal. Centuries later, the stone, encased in a statue, is discovered when the statue is broken apart in a loading accident.

A young gemmologist, Alexandra Amberson, examines the jewel to appraise it. But she unwittingly awakes the horrible Djinn inside. Soon the Djinn is loose on the streets, twisting people's wishes and killing them so he can steal their souls. Eventually the Djinn disguises himself as an elegant man-about-town, Nathaniel Demarest. In both human and Djinn form, he pursues Alexandra to trick her into making three wishes, to enable his unholy legions to conquer the Earth?