It is ten years after an aging Batman has retired, and Gotham City has sunk deeper into decadence and lawlessness. Now, when his city needs him most, the Dark Knight returns in. Joined by Carrie Kelly, a teenage female Robin, Batman takes to the streets to end the threat of the mutant gangs that have overrun the city. And after facing off against his tow greatest enemies, the Joker and Two-Face, for the final time, Batman finds himself in mortal combat...

Saitama is a hero who only became a hero for fun. After three years of 'special' training, though, he's become so strong that he's practically invincible. In fact, he's too strong, even his mightiest opponents are taken out with a single punch, and it turns out that being devastatingly powerful is actually kind of a bore. With his passion for being a hero lost along with his hair, yet still faced with new enemies every day, how much longer can he...