Because of its huge advertising campaign on bill boards and in metro stations 25 French critics called moviegoers to boycott L'AS DES AS. They argued that Belmondo would displace smaller, more important movies like Jacques Demy's UNE CHAMBRE EN VILLE. Belmondo answered in newspapers with the words of Jean Cocteau: "Critics like to blame those who hold their head a little bit higher than the others." And Belmondo added that he does movies only for audiences not for critics. A year later he said in an interview: "Critics say that my movies won't last. Who cares? I live now."
In the German version Hitler (Meisner) speaks in front of his generals at the Obersalzberg about a detergent named Akropatz ("Gentlemen, only Akropatz makes a pot really clean!"). In the french version he speaks about his plans for invasion. In a second scene he says that somebody has sent him tights: "...and I hate tights!" In the original version Hitler asks for "more living space for the growing German race".
The second highest grossing movie of the year in France, beaten only by E.T. the Extra-Terrestrial (1982).
Broke the opening admissions record in Paris selling 463,028 tickets in its first week.
At the end of the movie, the SS guards are actually American extras, as the German ones didn't want to cut their hair for the role.