Houtaro Ichinose and his friends continue their search for the Chemies, and Ace Ukiyo and his friends confront the Jyamato, who have appeared again, when suddenly the "Strongest Level 10 Chemy", X Wizard appears. Its mysterious magical powers have transformed Keiwa Sakurai and the others into the form of Chemies. In addition, as many as five "Strongest Level 10 Chemies" and the Geats Chemy, which looks just like Kamen Rider Geats, will appear at the same time. Perplexed by the series of unusual situations, Houtaro and his friends, Ace, and Keiwa, who has been turned into a Chemy, form teams to take on the "Strongest Chemy Capture Game". What is the terrifying purpose hidden in this game? What is the mystery behind Geats Chemy's appearance? Will Kamen Rider Gotchard and Kamen Rider Geats be able to clear the hurdles that await them...?