The 13-year-old son of a famous toy designer who passes away before completing the machine of his dreams: the "Yatter-Wan", a dog-shaped all-terrain rescue robot. It is up to Gan, who is actually quite a bit of genius at mechanics, to complete his father's dream. He then formed a fighting team named "Yatterman" with his girlfriend Ai, and naming himself "Yatterman No. 1".