Marlon Brando said that he found co-star David Niven so funny, he often broke into uncontrollable laughter during filming, thus ruining many takes. It was so bad that he would have to force himself not to look Niven in the eye during filming.
Beaumont Sur Mer is the fictional name given to Beaulieu-sur-Mer - a resort town, between Nice, France, and Monaco, on the French Riviera.
Remade into "Dirty Rotten Scoundrels" with Steve Martin & Michael Caine, almost word for word the same - except for the 'twist' ending.
Before Marlon Brando and David Niven, Universal Pictures had lined up Gregory Peck and Tony Curtis for the leads in this movie; they had both co-starred the previous year in Le combat du Capitaine Newman (1963). Curtis had been one of Universal's most successful contract players, and Peck had just won the Oscar and given them a huge box-office success with Du silence et des ombres... (1962).
First cinema film of veteran TV comedy director Ralph Levy. (He only made one other, the following year's "Do Not Disturb").