In the anime's story, Hiroto longs to build a secret base near his house, and in his house's storeroom he meets a ninja and "Nintuber" named Tonkachi. Tonkachi, who knows about the existence of the "Ninja Box," forces Tonkachi to go to the "Village of Tatemakuri," where they meet a talking dog named Tatezou.
(Source: ANN)