Goofs

Dr. Mabuse rips a telephone from its cord and throws it on the ground, in a later shot the telephone is still on the table and intact.

When The Blonde Luck (Marielouise Nagel) gets down to pick up her purse, Commissioner Kras (Gert Fröbe) gets up from his bar stool behind her twice.

When the car of Henry B. Travers and Peter Cornelius turns around the corner, the inside shots still show a long straight street behind them.

When Commissioner Kras chases the perpetrator in a police car, during the part in the city the shop signs in the background are reversed - an indication for a reversed back projection.

Right in the first shot, Barter's Borgward and the cars around him are supposed to be driving, suggested by the movements of the cars in the background. When the shot widens however, the rear wheel of his car isn't turning - a clear indication of a back projection.

When Travers' Assistant brakes for the crossing Cornelius, Travers reacts much too late. Together with the not-so-elegant back projection this is an obvious hint at the fact that the car is stationary and Peter van Eyck reacts badly to a cue.

(German original version) When Commisioner Kras meets Berg at the Bar the first time, Andrea Checchi for a short instance is not dubbed over and his real voice can be heard saying the English word "hello".

(German original version) When Henry Travers clinks glasses with Marion Menil in the hotel room after the seance, Peter van Eyck can still be heard saying "cheers" under the dubbed over German "zum Wohl".

In the cellar, Mabuse tells his henchmen to close the vault door, yet he himself holds the remote control in his hand that he used before to open the door.