Professor Grant signs a contract with Dr. Selin for the sale of his invention of cold light with the plans for his invention being kept in Grant's apartment. The negotiations are secretly heard by the illusionist Durk, who wants to seize the invention. A few days later Selín is found dead, killed by a light bulb filled with poisonous gas. Durk performs at the birthday party of Grant's daughter Anna and seizes the plans for the invention.
as Professor Oskar Grant
as Anny Grant
as Ing. Milan Bell
as Dr. Karel Selín
as Durk, the Magician
as Ferdinand Kardan
as Martin Bálek
as Baron Evans Margus / Servant
as Jan
as President of Police
as Hynek, reporter
as Grant's Assistant
as Hall
as Selín's Companion
as Gatekeeper
as Seance Guest
as Seance Guest