Karl Ludwig Diehl, Lester Matthews, Georg C. Klaren, Frank Vosper, Herbert Juttke, Greta Nissen, Don Alvarado, Arthur B. Woods, Robert Baberske, Max W. Kimmich

On Secret Service is a movie starring Greta Nissen, Karl Ludwig Diehl, and Don Alvarado. Greta Nissen stars as an Italian noblewoman living a dangerous double life as a spy. A remake of the celebrated German thriller Spione am Werk....