Mikado Ryūgamine is a young boy who longs for the exciting life of the big city. At the invitation of his childhood friend Masaomi Kida, he leaves home to go to a high school, Raira Academy, in Ikebukuro, Tokyo.
Masaomi warns him about people he doesn't want to cross in the city: a violent and superhumanly strong man dressed like a bartender, an information broker, and a mysterious gang called "The Dollars." And, to top it off, Mikado witnesses an urban legend on his first day in the city: the "Black Rider," the supposedly headless pilot of a black motorcycle that sounds like a horse.
The narrative follows all of the characters equally, showing how their lives intersect, creating a greater plotline from what each character knows about a common incident.