In order to save the drama club, Houtaro and his friends decide to help put on a performance of "Romeo and Juliet". Mikuriya, the head of the club, selects Houtaro to play Romeo, while Seina, a transfer student and childhood friend of Houtaro, runs for the role of Juliet, while Rinne is put off by the fact that she is not a member of the club.

Rinne is bothered by Houtaro and Seina's sudden closeness. Atropos appears, sees through Rinne's emotional turmoil, and unleashes a Malgam. Rinne desperately defends Seina who is nearby...!

"Kudo! Fight like you are!"

With the advice of Minato, Houtaro and Rinne manage to escape their predicament, but Rinne's feelings and the future of the "Romeo and Juliet" production become uncertain.

Furthermore, Atropos appears with a new Malgam. Houtaro and Rinne transform into Riders, but Majade strikes them with a powerful blow...!

Gotchard defeats the Malgam, who threatens the people, but the people of the city still fiercely condemn Chemies and the alchemists. A world where people and Chemies can live together.... Houtaro has no end to his worries.

Supana has lost his driver, and Gigist calls on him to fight with him. Supana refuses, and fights as Valvarad, but is engulfed by the black flames that Gigist unleashes. Supana foresees his own demise... but then!?

Glion, transformed into Kamen Rider Eld by the power of the Philosopher's Stone, summons an army of Dreatroopers. The city and its people are transformed into gold, and El Dorado is steadily approaching completion.

Houtaro tells his mother, Tamami, that as a Kamen Rider he will create a future where humans and Chemies can live together, and that he doesn't want to run away from his Gotcha! He then joins Rinne, Supana, and the other Chemies in a final battle to defeat Glion!