Komaru Naegi, the younger sister of Makoto Naegi, has spent more than a year held captive in an apartment in Towa City, cut off from the outside world. Her confinement ends abruptly when a murderous Monokuma robot breaks into her room and she discovers a city thrown into chaos, its adults hunted by swarms of the machines. The uprising is the work of the Warriors of Hope, a group of children determined to exterminate every grown-up and build a world of their own. Armed with a strange megaphone weapon and joined by the troubled Toko Fukawa, Komaru must fight her way through the ruined streets in search of a way out.