O vice-oficial da Aliança das Nações Unidas, Simon Marcus, que pretende conquistar o mundo com a organização terrorista Downfall junto com o cientista louco Keiji Uraga, ataca os Kamen Riders com força esmagadora. É apenas em Kamen Rider Grease que as habilidades do inimigo não funcionaram. Para derrotar este novo inimigo e resgatar Misora, Kazumi Sawatari deve criar um novo item... mas é dito que isso requer a vida de seus amigos, os Três Corvos. A decisão final deve ser tomada.
A woman was killed by a truck wheel, which flew off while the vehicle was in motion. As the freight company which owns the truck becomes the target of the public and the media’s wrath, Tokuro Akamatsu, the president of the freight company, realizes that a structural defect within the truck itself may have been to blame. A conspiracy of the wheel manufacturer's attempts to cover up a defective product is uncovered.
