In the distant past, a monstrous devil was shattered after a devastating battle. Today, the splinters of that powerful foe are still causing chaos throughout the universe. While the Ultra Heroes fight to restore peace to the galaxy, a mysterious new threat uses these splinters in it's despicable schemes to destroy planets one by one. And now, that evil being is approaching the Land of Light. In it's way stands the gallant Ultraman Zero and his disciple, Ultraman Z (Zett). At the end of a fierce battle, Z pursues the monster alone, making his way towards Earth... Meanwhile on Earth, the anti-monster robot force STORAGE has been formed to deal with regular monster threats, and has just been joined by it's newest recruit, hot-blooded youth Haruki Natsukawa. When a monster from space invades Earth, Z and Haruki have a fateful encounter. Here begins the incredible story of our two young heroes' battles!