Hitoshi Nakamura, a salesman for Mekama Fire & Marine Insurance, is given Silver Power and the transformation substance Hera&Bo by an Alpha planetoid who suddenly appears on his way home from overtime work, giving him the ability to transform into Bravo-Man. As a first step toward world domination, a robot army led by the evil genius scientist Doctor Bomb invades Nitta Fourth Street. Bravo-Man challenges the robot army to a battle.

Hitoshi Nakamura, a salesman for Mekama Fire & Marine Insurance, is given Silver Power and the transformation substance Hera&Bo by an Alpha planetoid who suddenly appears on his way home from overtime work, giving him the ability to transform into Bravo-Man. As a first step toward world domination, a robot army led by the evil genius scientist Doctor Bomb invades Nitta Fourth Street. Bravo-Man challenges the robot army to a battle.