|Soji Tendo has trained seven years while waiting for the Kabuto Zecter in order to be Kamen Rider Kabuto. He wants to destroy all Worms while meeting other Riders with mysterious origins of how they got there. He meets Arata Kagami, who later becomes Kamen Rider Gattack, the two work together to save humanity from the alien Worms that arrived from a meteorite seven years ago. But 35 years ago, a certain species of Worm known as the Natives, created the Zecters. This compilation of mobile systems, also known as the Masked Rider System, affects space and time. The Zecters appear instantaneously from the ZECT headquarters to the selected personnel so that they may transform into the respective Rider to fight the Worms. Most of the Riders possess two forms such as the huge armor known as Masked Form and the sleeker Rider Form, which can use the Clock Up, that allows the Rider to move at high speed.