This is the story of Yentown, a Tokyo ghetto inhabited by immigrants from all over Asia. The story revolves around a group of poverty-stricken immigrants, to whom a sudden twist of fate gives the opportunity to literally make money and thus realize their dreams. Shot with handheld camera, tinted with laughter, violence, sadness and imagination, Swallowtail Butterfly is impossible to be pinned down to a single genre. Juxtaposing the music of Frank Sinatra and Yentown Band is only of the many eccentricities found in the film.