With the promise of great power, and fueled by a desire for revenge, Shigeru undergoes surgery to become one of Black Satan's super soldiers.

Secretly, Shigeru knows that Black Satan was responsible for Numata's murder, and he uses the organization as a means to gain the power he needs to exact his vengeance.

Shortly after his escape, Stronger meets Yuriko Misaki, another cyborg soldier created by Black Satan who can transform into Electro-Wave Human Tackle.

Later, the six previous Kamen Riders return to Japan and join Stronger to finally topple the evil Delza Army.

)), first broadcast on January 3, 1976 (one week after the series' finale) opens with Tobei Tachibana taking some children to a Kamen Rider roadshow.

When it's revealed that the monsters onstage are real and not actors, the Riders transform to save the crowd and Rider actors, uniting their power to defeat a surviving Delza Army general, Great Generat Darkness (暗黒大将軍, Ankoku Daishōgun) in his hideout beneath the stadium.