Filmed in late 1979, but not released for another three years.
Sir Rex Harrison was paid seventy-five thousand dollars for this, his last theatrical movie.
The bulk of this movie was filmed in the Netherlands with the Cinetone Studios in Amsterdam as a home base and production offices. Various interior and exterior locations in and around Amsterdam doubled as a.o. Munich, Hamburg, Budapest, Hungarian puszta, French-German border, and the French countryside. The production value of these locations is actually very high.
Just a week after it appeared in the airport scene where Michael Rogan (Edward Albert, Jr.) comes off the plane in Munich Airport (filmed at Airbase Gilze-Rijen in the Netherlands), the A-26 Invader, flown by Don Bullock, crashed at a Battle of Britain remembrance airshow at London Biggin Hill Airport, killing all crew and passengers. In a twist of fate, several crew members of this movie, who were invited to fly with Don as passengers at the airshow, were unable to join due to their shooting schedule.