Supposedly based on the Monster of Dusseldorf, its working title was Murderer Among Us.  
Supposedly based on the Monster of Dusseldorf, its working title was Murderer Among Us.  Paul Kemp plays a pickpocket with six watches, and Georg John plays a blind beggar who unravels the mystery.  Inspector Karl Lohmann and Police Commissioner Groeber consort to capture the main character, and earn the assistance of other criminals.  The murderer is done in by his constant whistling of In the Hall of the Mountain King whenever he struggles to control himself.  Centering on the child murderer Hans Beckert, FTP, name this 1931 Fritz Lang film starring Peter Lorre.
Supposedly based on the Monster of Dusseldorf, its working title was Murderer Among Us.  
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