Hamtaro is the little pet hamster belonging to the fifth-grader, Laura. Her family has just moved to a new home and it isn't long before Hamtaro has slipped out of his cage to explore his new surroundings. He meets the Ham-Hams, (the other hamsters in the neighbourhood), the group decide to build their own clubhouse where they can hang out together. Hamtaro and the Ham-Hams are always going on big adventures as they try to help their unsuspecting owners in any way little hamsters can.