Pieces of a mysterious artefact known as the Skull Stone are scattered across the planet, and they hold the power to reveal the location of the largest deposit of gold in the world. The Doronbo Gang, the villainous trio of the series, are on pursuit of fame, power and wealth as they search for the Skull Stone. However, their plans are constantly foiled by Yatterman, a heroic, mecha-riding duo of youngsters.