A young boy Naoto Tajima was hit by the bike of the Saturn biker gang and seriously injured. His desire for vengeance possessed his Ultraseven doll and turned into a giant, dubbed “Delusion Ultraseven”. Delusion Ultraseven is extremely strong and adept at fighting with kicks.

Naoto was hospitalized. The night his condition worsened, Delusion Ultraseven appeared before the members of the Saturn gang. The fake Ultra grabbed a gang member on his bike and threw both away, injuring the member. After that, the UGM hesitated to attack since the fake Ultra looked just like the real Ultraseven, the fake Ultra chased after the other gang members. Delusion Ultraseven destroyed several buildings and the surrounding area until Ultraman 80 arrived to engage it in combat.

Delusion Ultraseven gained the upper hand, using swift movements and kicking many cars at 80. Ryoko Hoshi aka Yullian learned with her psychic abilities that the fake Ultra was being controlled by brain waves. Once 80 heard this, he convinced Naoto to let go of his vengeful feelings which stopped the fight. With Delusion Ultraseven and Naoto now separated, 80 grabbed the fake Ultra and flew with it off into space.