An animated Pink Panther was created for the opening credits because writer and director Blake Edwards felt that the credits would benefit from some kind of cartoon character. David H. DePatie and Friz Freleng decided to personify the film's eponymous jewel, and the Pink Panther character was chosen by Edwards from over a hundred alternative panther sketches. The Pink Panther introduced in the opening credits became a popular film and television character in his own right, beginning with the cartoon short The Pink Phink (1964) the following year.
Blake Edwards and Peter Sellers enjoyed working together to develop Clouseau down to every move and nuance of voice and expression. "For years I'd been getting bits of what I wanted into films, as writer or director . . . but I had never had an area in which to exploit my ideas to the full," Edwards said. "Then along came Peter, a walking storehouse of madness, a ham with an almost surrealist approach to the insanity of things, and we found an immediate affinity."
Blake Edwards wanted Audrey Hepburn to play The Princess. Hepburn declined but she suggested that he cast her friend, Claudia Cardinale.
In the bath scene with Capucine and Robert Wagner, an industrial-strength foaming agent is used, which burned both of the stars' skin. Wagner, who was completely immersed at one point, became blind for four weeks.
With just two weeks to go before shooting begun, the producers decided that Ava Gardner's erratic lifestyle could affect filming and decided not to offer her the part of Madame Clouseau. Capucine was hired in a hurry, but Peter Ustinov's wife felt this would affect the calibre of the production and told him to withdraw . From this chaos, Peter Sellers became an international superstar.