A mysterious stone known as Skull Stone (ドクロストーン, Dokurosutōn) is scattered across the planet, it holds the power to reveal the location of the largest deposit of gold in the world. A trio of villains, the "Doronbo (ドロンボー, Doronbō) Gang is in pursuit of fame, power and wealth as they search for the Skull Stone. The "Yatterman" try and block the Doronbo every chance they get.
Gan Takada is a 13-year-old boy whose father is a famous toy designer who failed to complete the "Yatter-Wan", a dog-shaped all-terrain rescue robot. Gan is an expertise in mechanics, and he helps fix his father's dream design. He forms a fighting team with his girlfriend Ai, and names himself "Yatterman No. 1". His weapon of choice is a kendama, which he uses as a flail and grappling hook as well as for his special attack "Kenda-Magic"
Ai Kaminari is Gan's girlfriend, and the only daughter of a shopkeeper who sells electrical appliances. She is Gan's loyal follower. She is often seen constructing and modifying machines with Gan. She is "Yatterman No. 2", and uses a telescoping baton to emit electric currents to shock opponents, as well as for her special attack "Electric Stick".