During this period, Hollywood stars such as Gregory Peck and Victor Mature moved to Europe to avoid paying punitive US tax rates. Richard Widmark decided to film in the UK for the same reason.
The bubble car is a Messerschmitt KR175. They were built from 1953 to 1955. It's the same type of car used in Brazil (1985), Kenny Starfighter (1997), and The Addams Family (1991) (as driven by Cousin It).
The unloading of boxes of gold was filmed at Blackbushe airfield. The three-ton lorry they were loaded into was provided by the Royal Military Police (RMP). The RMP London District Provost Company provided extras for the day during the filming of these scenes.
The film's premiere at the Odeon Theatre, Leicester Square, London, was in aid of the Royal London Society for the Blind. Those who attended included Mr. and Mrs. Nigel Patrick ( Beatrice Campbell), US Ambassador [xxxxxxx], Columbria Pictures Managing Director Max Thorpe and Sales Manager E. Bryson. Representing Warwick Film Productions was Executive Producer Irving Allen.