Daibazaal has an ambitious plan to squash the planet’s uniting in resistance by creating an army of Mecha Beastmen produced at a factory on a secret Planet Midway. Princess Amue slips away from Planet Heracles in order to help Ryou organize a guerilla army against Galra and report their findings to the GoLion team on Altea. Ryou disguises himself as a Beastman and infiltrates the secret factory, revealing its location to the GoLion team who must take on an Ultra Giant Beastman Alpha and destroy the Beastman factory before it’s too late.