A girl named Laura, her parents, and her hamster Hamtaro move into their new house. Hamtaro goes outside and meets hamsters Oxnard, Boss, and Bijou, who Hamtaro is instructed to sing for.
Boss introduces Hamtaro and Oxnard to his friends Pashmina, Penelope, Howdy and Dexter, and discover Snoozer. The hamsters convert Boss' house to the Ham-Ham Clubhouse.
Pashmina and Penelope introduce their friends Maxwell, Panda, Sandy and Cappy. Howdy and Dexter make a mess of the Clubhouse, and are booted out by Boss.
Laura introduces Hamtaro to candies called Diamonds of Sugar. Boss says the candies are actually stars, and the Ham-Hams want to catch the supposed Diamonds of Sugar from the sky.