Ultraman and his comrades from M-78 (including a new Ultraman, Zero, the son of Ultra Seven) join forces with other allies to fight a massive army of giant monsters led by the evil Ultraman Belial.

Ultraman Zero, the rookie Ultraman from Tsuburaya Productions’ 2009 theatrical movie returns, and getting full-fledged. However, he is confronted with the empowered Kaiser Belial, back from the evil Ultraman Belial whom he and other Ultraman warriors battled so hard on the m-78 Planet. Can Ultraman Zero live to the expectations of his legendary father Ultra Seven? Check it out in the latest Tsuburaya Productions’ action packed movie.

Ultraman Saga opens with a powerful apocalyptic vision of Tokyo, buildings destroyed and the city seemingly devoid of life. We are soon introduced to the Earth Defense Force (EDF), Team U (played by members of the female idol group AKB48). They and a group of young children and the last survivors on planet Earth after the world was invaded by the evil Alien Bat, the rest of the human population having been abducted.

Zero sits on a cliff while he watches a strange tower firing lightning bolts, and then rises to face against what it seemed to be members Ultra Brothers, Ultraman, Robot Zoffy, Ultraman Jack and Ultraman Ace. After incapacitating the ZAP SPACY's Space Pendragon, Ultraseven joined the group as they face against Zero.

Zero finds himself trapped within a universal gap and faced against an impostor Ace. Following the battle, Darklops Zero was restrained once more by Herodia, remembering a figure named "Kaiser Belial" before deactivating. Rei was restrained after his failed attempt to intrude the alien base but was rescued by none other than his alternate self. Unlike the prime Rei, alternate Reimon was never able to control his powers, forced into the state of Reionic Burst until the original Rei punched Reimon, thus deactivating its Reionic Burst mode. Rei revealed that he lost his Rayblood instinct after Hyuga threw Seven's Eye Slugger, creating a scar on his chest which symbolizes the former's friendship with ZAP SPACY members. While searching for Rei, Hyuga instead finds his Neo Battle Nizer and an entrance to the alien base made by Litra. Although the fake Ace was destroyed, Zero try to find an escaped but was halted by Seven and Ultraman impostors.

One year after the battle with Belial's Galactic Empire, the members of Ultimate Force Zero returned to Planet Esmeralda to see Princess Emerana. They arrived to see her and Jean Bot captures by a mysterious artificial planet which then took of for another universe. In the Universe where the sphere fled to, Zap Spacy members Rei and Hyuga are forced to infiltrate it, as it is on a collision course with Planet Bram. Inside they encounter various robot monsters, that the Ultramen have fought in the past, all under the control of Beatstar, with one mission: "Destroy all organic life". After saving Emerana, they encounter a robot very similar to Jean Bot, Jean Killer. During their fight with Jean Killer, Zero learns from Jean Bot that Jean Killer is actually his twin brother. Ultimate Force Zero must now put a stop to Killer's rampage and defeat Beatstar in the process. This is part 1 of a 2-part special release to promote the movie Ultraman Saga.

One year after the battle with Belial's Galactic Empire, the members of Ultimate Force Zero returned to Planet Esmeralda to see Princess Emerana. They arrived to see her and Jean Bot captures by a mysterious artificial planet which then took of for another universe. In the Universe where the sphere fled to, Zap Spacy members Rei and Hyuga are forced to infiltrate it, as it is on a collision course with Planet Bram. Inside they encounter various robot monsters, that the Ultramen have fought in the past, all under the control of Beatstar, with one mission: "Destroy all organic life". After saving Emerana, they encounter a robot very similar to Jean Bot, Jean Killer. During their fight with Jean Killer, Zero learns from Jean Bot that Jean Killer is actually his twin brother. Ultimate Force Zero must now put a stop to Killer's rampage and defeat Beatstar in the process. This is part 2 of a 2-part special release to promote the movie Ultraman Saga.

After the events of Ultraman Saga, Ultraman Zero goes to the Monster Graveyard to train with his new powers. There, Zero encounters Alien Bat Glacier; a follower of the original Bat that took over the alternate world. He revives the monster army, the Four Beast Warriors of Hell from the Graveyard to fight Zero for defeating his leader.