Set two years after the events of Ultraman Ginga, the story follows Hikaru Raido as he joins the newly formed special defense team, UPG (Ultra Party Guardians). The team is tasked with investigating mysterious incidents involving Spark Dolls and protecting the Earth from new threats. The conflict intensifies with the arrival of the alien invader Alien Chibull Exceller, who seeks to harness the power of Victorium, a mysterious energy source hidden deep within the Earth. To protect the Victorium and the planet, Hikaru encounters Shou, a warrior from the subterranean Victorians who transforms into Ultraman Victory. Initially clashing due to their differing philosophies, Hikaru and Shou must learn to work together as Ultraman Ginga and Ultraman Victory to combat the forces of the Vict Lugiel and other powerful monsters. The series explores themes of cooperation, the protection of nature, and the responsibility that comes with great power.