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...

Rena Sayama's world has been turned upside down by the discovery that the man she believed to be her father actually isn't. Even more stunning is the revelation that she too has the power to wear the Ultraman suit! Meanwhile, a secret group within the Star Cluster Council arrives on Earth with a sinister mission--the complete eradication of the Ultramen!