The Pink Panther is a heroic, moral cartoon cat with pink fur and the manners of an English aristocrat. He only becomes flustered or angry at obtuse or offensive humans who try to disrupt his existence, or at troublesome gadgets, rodents, or insects. In most of his cartoons, he stumbles into a difficult situation and stoically endeavors to make the best of it. Episodes of this series feature three theatrical cartoons, two with the Pink Panther, and one featuring the Inspector, a cartoon version of the accident-prone, bumbling French detective, Inspector Clouseau, played in movies by Peter Sellers. The Inspector is often assisted by a Spanish gendarme, Sergeant Deux-Deux, and together they fallibly battle villains of all shapes and sizes in various parts of the world, always on the orders of the long-suffering Surete Commissioner.
Inspector Clouseau (Peter Sellers) of the National Police (France), the French national police, is called to the country home of millionaire Benjamin Ballon (George Sanders) to investigate the murder of his chauffeur, Miguel Ostos. The chauffeur was having an affair with one of the maids, Maria Gambrelli (Elke Sommer), and attacked her in her bedroom after she broke off with him. Miguel was shot and killed in her bedroom and Maria was found with the smoking gun in her hand, but claims no knowledge of how it got there as she maintains she was knocked unconscious. All evidence points to Maria as the killer, but Clouseau is convinced of her innocence because he has developed an immediate attraction to her. Realizing Clouseau has been inadvertently assigned to a high-profile case, Commissioner Dreyfus (Herbert Lom) has him removed and personally takes charge of the investigation.
In the fictional country of Lugash, a mysterious thief seizes the Pink Panther diamond and leaves a white glove marked with a gold-tinted "P". With its national treasure once again missing, the Shah of Lugash requests the assistance of Inspector Clouseau of the Sûreté, as Clouseau had recovered the diamond The Pink Panther (1963 film). Clouseau has been temporarily demoted to beat cop by his boss, Chief Inspector Charles Dreyfus, who despises him to the point of obsession, but the French government forces Dreyfus to reinstate him. Clouseau joyously receives the news after fending off a surprise attack from his servant Cato, who had been ordered to do so to keep the Inspector on his toes, and duly goes to Lugash.
At a psychiatric hospital, former Chief Inspector Charles Dreyfus is largely recovered from his obsession to kill the new Chief Inspector Jacques Clouseau and is about to be released when Clouseau, arriving to speak on Dreyfus' behalf, within minutes drives Dreyfus insane again. Dreyfus later escapes from the hospital and once again tries to kill Clouseau by planting a bomb while the Inspector (by periodic arrangement) duels with his manservant Cato. The bomb destroys Clouseau's apartment and injures Cato, but Clouseau himself is unharmed, being lifted from the room by an inflatable disguise. Deciding that a more elaborate plan is needed to eliminate Clouseau, Dreyfus enlists an army of criminals to his cause and kidnaps nuclear physicist Professor Hugo Fassbender and the Professor's daughter Margo, forcing the professor to build a "doomsday weapon" in return for his daughter's freedom.
Philippe Douvier (Robert Webber), a major businessman and secretly the head of the French Connection, is suspected by his New York Mafia drug trading partners of weak leadership and improperly conducting his criminal affairs. To demonstrate otherwise, Douvier's aide Guy Algo (Tony Beckley) suggests a show of force with the murder of the famous Chief Inspector Jacques Clouseau (Peter Sellers).
As a child in Lugash, Princess Dala receives a gift from her father, the Maharajah: the "Pink Panther", the largest diamond in the world. This huge Pink diamond has an unusual flaw: looking deeply into the stone, one perceives a tiny discoloration resembling a leaping panther. Twenty years later, Dala has been forced into exile following her father's death and the subsequent military takeover of her country. The new government declares her precious diamond the property of the people and petitions the World Court to determine ownership. However, Dala refuses to relinquish it.