With his handsome slim-fit suit, characteristic glossy shades, and a casual cigarette in mouth, word is that the remarkably strong Shizuo Heiwajima rules Ikebukoro's streets. When ordinary bartender Shizuo Nobusuma hears these rumors, he realizes he could make his own life a bit easier: as a con artist.

Donning a blond wig and venturing into Ikebukuro assuming Shizuo's identity, the impostor is confident he is fooling everyone into doing his bidding. But as the district's residents either take pity or tease him before the actual Shizuo inevitably finds out, his luck plummets when he encounters Izaya Orihara—an information broker whose favorite activity in the world is messing with Shizuo.

Durarara!!x2 Ketsu: Dufufufu!! adapts a chapter from Durarara!! Gaiden!?, which was released to commemorate the series' 10th anniversary. The OVA was pre-screened in theaters on May 21, 2016 and later included with the sixth Blu-ray and DVD volume of Durarara!!x2 Ketsu, released on July 27, 2016.