AllMovie

Popular German film star Hans Albers plays the brother of drug-addicted opera star Gerda Maurus. When Albers takes Gerda to a sanitarium, they both become targets of slimy dope peddler Peter Lorre, who fears that Gerda will blow the whistle on him. Lorre kidnaps the woman, leading Albers on a frantic chase. With the help of another opera singer (Trude von Molo), Albers discovers the secret behind Lorre's drug-smuggling operation, rescues his sister, and exposes the respectable "Mr. Big" behind the whole narcotics racket. Filmed in Germany, White Demon (Der Weisse Damon) was also lensed in a French-language version, which also costarred Peter Lorre.