Deputy Officer of the United Nations Alliance, Simon Marcus, who pursuits to conquer the world with the terrorist agency Downfall along with the mad scientist Keiji Uraga, assault the Kamen Riders with overwhelming power. It is simplest on Kamen Rider Grease that the enemy's competencies did not paintings. In order to defeat this new enemy and rescue Misora, Kazumi Sawatari should create a brand new item ... However it's far advised that it requires the life of his pals, the Three Crows. The remaining decision should be made.