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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.
It’s August 6th, and it's a very special day: Hamtaro’s birthday! After Laura tells him about his long lost mother, Hamtaro, Boss and Oxnard set out to find her in the town of Sumire – but it will take three thousand hammy steps to reach their destination! Along the way they encounter urban delights and sunflowers galore. In the meantime, the rest of the Ham Ham gang plan out a birthday party for their furry friend, sending out invitations far and wide. Happy birthday, Hamtaro!