Hamtaro Hai!

5th-grader Hiroko Haruna owns a hamster, and his name is Hamtarou. After moving into a new town, Hamtarou finds that he's in the company of lots of different hamsters, making up a group of hamster friends that go on crazy adventures through the city. Before they save Hiroko and other humans from nasty predicaments, however, they have to learn how to save themselves.

As Laura heads out to summer camp, Hamtaro and Oxnard come across a young girl by the name of Haibi, who's trying to find the ocean. Haibi found a treasure map while searching through the storage burrow and is now willing to find the treasure to help her heat exhausted granny. The Ham-Hams, who are more than willing to help her, pack their things and set out to find the treasure.

Considered the prequel to the fourth Hamtaro game (fifth in Japan). In this tribute to the 2004 Olympics, Hamtaro and the Ham-Hams are tasked by Prince Bo with lighting the everlasting torch to Hamcropolis. However, the Rainbow Girls will not allow this and pursue the Ham-Hams.

A direct continuation of the Tottoko Hamtarou series, introducing new characters.