A young man named tE-rU  is causing a commotion in the city. When he goes inside the mechanical giant Rudian it begins to march on the city. But after seeing tE rU heal an injured girl, Daichi unites with Ultraman X and attempts to stop Rudian.

The fearsome monster Zetton attacks! Despite trying his various armors, Ultraman X is left completely defeated. In order to prepare for Zetton's next strike, Daichi focuses on developing a new armor. He then meets Dr. Touma, who offers to help.