Der Frosch mit der Maske on AllMovie

That cornucopia of crime fiction Edgar Wallace is plundered once more in The Fellowship of the Frog. The villain is a mysterious master criminal known only as "the Frog," whose henchmen border on the fanatic in their devotion to their leader. A Scotland Yard inspector (Siegfried Lowitz) makes it his life's mission to bring the Frog to justice. Confounding the inspector at every turn is an amateur detective (Joachim Fuchsberger), who may not be all that he seems. Also known as Face of the Frog, this German mystery melodrama was originally released as Der Frosch mit der Maske.