The Shiranui Clan have planned for 2000 years to conquer Japan in retaliation for their nomadic ancestors being banished from the country by the Yamato Clan. Each armored ninja-like member of the clan controls a gigantic robot warrior in order to overthrow the "Yamato Government," as they call it. In response to this terrorist threat, Japan's National Security Organization send agent Gentaro Shizuka, disguised as what can best described as a Spaghetti Western version of a singing cowboy...