The entire Moomins clan embarks on a hilarious adventure to the glamorous Riviera. Snorkmaiden is dazzled by the attention of a playboy and Moomin learns that jealousy’s sting can be terribly painful. When Moominpappa befriends an aristocrat and adopts the name ‘de Moomin’, an exasperated Moominmamma retires to the relative calm of their trusty old boat, to wait for her family to come to their senses. For the very first time, the unity of the Moomins is threatened.