David Niven recreates a little of his "Raffles" (1939) character here as the suave and debonaire "Sir Charles Lytton". He's a social sophisticate who is invited to the grandest of soirées and where there is always a jewel robbery. Nobody has ever quite put two and two together before until "Clouseau" (Peter Sellers) and his wife "Simone" (Capucine) arrive at a luxurious hotel where the "Princess" (Claudia Cardinale) is also staying - along with her priceless necklace. "Clouseau" thinks it's bound to be stolen, as does just about everyone else but the arrival of nephew "George" (Robert…