Houichi Kano, the grandson of the world-famous inventor Hosuke Kano, is a student at Houwa High School in Musashino City. On the tenth anniversary of first contact with the Riofaldians, the unveiling of an Elevator Ship designed for orbital transport between the Riofaldian homeworld and Earth is about to take place. However, this is merely a ploy to seize control of Earth by leveraging their advanced technology and the large Riofaldian workforce already present on the planet. It is now up to Houichi, aided by Housuke, his school friend Akane, and Isaka, to stop them and save Earth. The series features plenty of mecha mega-robot action, state-of-the-art gunsuits, sexy shape-shifting androids, and the reason why the manga is called Cannon God... But the Riofaldians are one step ahead, and they have a plan...