Mikado Ryūgamine, a young boy who longs for the exciting life of the big city, moves to Ikebukuro to attend Raira Academy with his childhood friend Masaomi Kida, whom he has not seen since he was young. After the two meet at the train station, they set out to explore the streets of Ikebukuro.
Masaomi warns Mikado about people he does not want to cross in the city such as the violent and superhumanly strong man Shizuo Heiwajima, the information broker Izaya Orihara, and the mysterious gang known as "The Dollars." After running into some of the side characters, Mikado sees a local legend called the "Black Rider" who rides around Ikebukuro on a black motorcycle that occasionally neighs like a horse and who is rumored to have no head under her helmet.
The "Black Rider's" real name is Celty Sturluson; she is an Irish dullahan who is in Ikebukuro looking for her stolen head while working as an underworld courier. The narrative follows all of the characters equally, showing how their lives intersect and create a greater plot line from each character's knowledge about a common incident.
The story is told from the perspective of approximately eleven of the main characters and changes every episode in the anime, sometimes even more often. One of the few constants given in every episode is that the narrator gives their own opinion on the current situation that they are in as well as what things that make them tick and keep them going in Ikebukuro: a city with a large underbelly that is the medium for the majority of both the plot's development and random violence throughout the series.