A first screenplay was written by Peter Ustinov, who was also the first choice for Dennis Price's role as Dunstan Dorcester.
First film acting of Jeremy Lloyd.
Much of it was shot by Cyril Frankel, as original director Robert Hamer, who was an alcoholic, kept showing up for work drunk.
The used car salesmen Dunstan and Dudley (Dennis Price and Peter Jones) were based on characters from the BBC radio comedy series "In All Directions" broadcast during the 1950s. The radio characters were known as Morry and Dud and were played by Peter Ustinov and Peter Jones who also wrote the scripts together with scriptwriters Frank Muir and Denis Norden. Their catch phrase "run for it!" was reprised in the film.