Saitama is out shopping with Genos in tow when the pair come across G4, a demonic robot on a mission to eliminate King. Elsewhere, Sitch attempts to recruit various cutthroats, villains and assassins of the underworld to help the Hero Association.

Goketsu, the first Super Fight Tournament champion, arrives in the stadium. Having now become a monster, he’s aiming to force the Super Fight competitors to turn into monsters themselves. When several do, it’s up to Suiryu to take them on alone.