In the year 2113, people are given brain scans to determine how likely they are to commit a crime. Those who fail are apprehended, or even killed.

Mikado Ryugamine moves to Ikebukuro at his friend’s invitation and quickly becomes entangled in the city’s dangerous underworld. After witnessing the legendary Headless Rider, he finds himself caught up in escalating violence and gang conflict that begin to throw Ikebukuro into chaos.