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The Series Durarara!! (デュラララ!!) is a 13-volume light novel series written by Ryohgo Narita and illustrated by Suzuhito Yasuda. There is both a manga and anime adaptation. The first season of the anime was produced by Studio Brain's Base and aired in winter 2010 in Japan and summer 2011 in North America, spanning 24 episodes and two OVAs. The second season, produced by Studio Shuka, was released in three separate cours that aired during winter 2015, summer 2015, and winter 2016. Each cour is 12 episodes long and includes an OVA. The North American release was produced by Aniplex USA, streamed on Crunchyroll, Funimation, and Hulu, and broadcast on Cartoon Network's Adult Swim.
The story takes place in Ikebukuro, Tokyo, and features a large cast of main characters, including a modern-day Dullahan, an anonymous internet-based gang called the Dollars, color gangs like the Yellow Scarves and Blue Squares, a demon sword known as Saika, information brokers, debt collectors, movie stars, high school students, yakuza, and many other colorful characters. As the Dullahan searches for her missing head, different sides converge and conflict escalates. The story follows the main characters equally as they affect and are affected by the events in the city around them.