Decades ago, a being known as the Giant of Light joined together with Shin Hayata of the Science Special Search Party to save Earth from an invasion of terrifying monsters called Kaiju. Now, many years later, those dark days are fading into memory, and the world is at peace. But in the shadows a new threat is growing, a danger that can only be faced by a new kind of hero--a new kind of Ultraman...

The Z-ton Core has arrived to wipe out anyone claiming to be Ultraman. Their leader, Temperor, lets it be known that the Ultramen were the true reason for the attacks on Earth in the past. Shinjiro can't believe it, and as his rage grows, his body seems overwhelmed with Specium energy. A question begins to spread among those watching the battle--what exactly is Ultraman?