During filming in London, James Coburn took time off to pose for the cover photograph of Wings third album, 'Band on the Run'.
Rolf Wanka was advised to change his surname for obvious reasons (too much like Wanker). However, he felt that the problem was other people's and refused.
The original script was more of a political thriller. However, the screenplay proved to be a quite considerable problem and was being rewritten constantly throughout filming. Interviewed by Michael Parkinson on late-night British TV, James Coburn said he was going round to see director Ken Hughes straight after the interview to try to get the ending of the film sorted out. Several reviewers later said that the ending eventually used seemed excessively contrived, whilst the film as a whole had difficulty in padding out its length to a 90-minute running time.
When Jean is introduced to Robert by the TV interviewer, she says, "Oh, we're old protagonists" - what she means, of course, is "antagonists".