Underclassmen from a rival group attack a Saitama biker crew in the Dollars' name, and Toramaru's leader Chikage Rokujou rides into Ikebukuro for payback, working over Dollars members for a line on whoever runs the group and colliding with Shizuo Heiwajima along the way. Mikado Ryuugamine, the Dollars' quiet founder, has his own problem when a first-year named Aoba Kuronuma works out the connection and starts angling for his time, while Celty Sturluson crosses paths with two Russian hitmen, one of them a girl who goes after Shizuo. This manga continues Durarara!! after the Yellow Scarves arc, ahead of the Durarara!!x2 anime.