In some official sources, not in the on-screen credits, Joachim Fuchsberger is mentioned among the cast under the pseudonym Blacky Wallace, which is a combination of his nickname and Edgar Wallace. For the adaptations of the latter's novels, Fuchsberger was most famous during the time.
The film was supposed to positively influence the image of the West German Federal Intelligence Service (BND) and so some personnel was involved in an consulting role. This was personally approved by Reinhard Gehlen, the president of the service at that time.