Wissenswertes

Russian soldiers on the east side of the Berlin wall purposely disrupted filming by using mirrors to reflect sunlight into the cameras. The scene where Harry Palmer (Sir Michael Caine) walks to Checkpoint Charlie for the first time had to be filmed from a long distance for that reason.

Harry Saltzman offered Eva Renzi a lucrative 200,000-British Pounds-a-year contract (the same he had signed with Michael Caine), but Renzi refused. After this film, Universal put her under contract. But her aggressive outbursts and difficult attitude on her first Hollywood set stopped her promising international career before it had really begun.

Hallam (Hugh Burden) tells Palmer (Sir Michael Caine) that he was with "Monty in '45". The "Monty" that Hallam refers to was British General Bernard L. Montgomery.

Eva Renzi and Guy Hamilton didn't get along very well. She thought he was an untalented director and told him how to light her, how to place the camera, and how to direct her co-stars. After two weeks of filming with her, Hamilton was about to quit.

Eva Renzi later said that this film ruined her reputation as a serious actress and prevented her from having a bigger career. (Which is pretty far from the truth, because this was the movie (her second appearance in a motion picture) that put her on the international map and got her the attention of Hollywood.)