The episodes of the anime series Gunslinger Girl are based on the Gunslinger Girl manga series written and illustrated by Yu Aida. The first series' episodes were directed by Morio Asaka, animated by Madhouse Studios, and produced by Bandai Visual, Marvelous Entertainment, MediaWorks, and Madhouse Studios. It adapts the first two manga volumes of the series over thirteen episodes which aired in Japan from October 8, 2003 to February 19, 2004 on Bandai Channel and Fuji Television. Set in contemporary Italy, the series tells about young girls who are turned into cyborgs, trained as assassins by adult male "handlers" and their missions against terrorists and gangsters on behalf of a secretive government agency.
A sequel called Gunslinger Girl -Il Teatrino, directed by Hiroshi Ishiodori and animated by Artland, aired in Japan on Tokyo MX TV from January 7, 2008 to March 31, 2008. It adapts the third, fourth and fifth volumes of the manga over fifteen episodes, with thirteen episodes airing on television and the final two released directly to DVD.