Durarara!! (デュラララ!!), often shortened to DRRR!!, is a Japanese light novel series written by Ryohgo Narita, with illustrations by Suzuhito Yasuda. Durarara!! tells the story of a dullahan working as an underworld courier in Ikebukuro, an internet-based anonymous gang called the Dollars, and the chaos that unfolds around the most dangerous people in Ikebukuro. The series ran for thirteen volumes, published by ASCII Media Works under their Dengeki Bunko imprint. A sequel series, titled Durarara!! SH and set two years after the events of the original series, started in 2014.
A manga adaptation of the same name, first illustrated by Akiyo Satorigi and later by Aogiri, has been serialized in Square Enix’s shōnen manga magazine Monthly GFantasy since July 2009. A 24-episode anime television series adaptation was broadcast from January to June 2010. It was followed by a 36-episode second season, titled Durarara!!×2, broadcast from January 2015 to March 2016.