Trail of the Pink Panther series regulars include Herbert Lom as Chief Inspector Dreyfus, Graham Stark as Hercule LaJoy (last seen in the 1964 Pink Panther film "A Shot in the Dark"), Burt Kwouk as Clouseau's faithful man servant Cato and André Maranne as Sgt. François Chevalier. "Trail" featured the animated opening and closing credits, animated by Marvel Productions and written and directed by Art Leonardi. Director Blake Edwards dedicated the film to Sellers, "the one and only Inspector Clouseau." Despite the dedication, Sellers' wife Lynne Frederick filed a $3 million lawsuit against the film's producers and the studio, claiming that the film diminished Sellers'
The Pink Panther derives its name from the eponymous pink diamond that has an enormous size and value. The diamond is called the "Pink Panther" because the flaw at its center, when viewed closely, is said to resemble a leaping pink panther. The phrase reappears in the title of the fourth film "The Return of the Pink Panther", in which the theft of the diamond is again the centre of the plot. The phrase was used for all the subsequent films in the series, even when the jewel did not figure in the plot. It ultimately appeared in six of the eleven films.