The Saint Seiya anime (also known as Knights of the Zodiac), based on the manga series of the same name by Masami Kurumada, was produced by Toei Animation. It first premiered on Japan's TV Asahi on October 11, 1986, and continued on until April 1, 1989. It was directed first by Kōzō Morishita (episodes 1–73) and then by Kazuhito Kikuchi (74–114). The character designers were Shingo Araki and Michi Himeno. Seiji Yokoyama composed the soundtrack. The chief scriptwriters were Takao Koyama (1–73) and Yoshiyuki Suga (74–114).
The anime is divided into arcs, similarly to Kurumada's original manga. The first is the "Sanctuary arc", which starts on episode 1 and ends on episode 73, followed by the "Asgard arc" (episodes 74–99). The Asgard storyline did not exist in the manga and was created especially for the anime. The third arc, the "Poseidon arc" (episodes 100–114), concluded the anime, leaving the final part of the manga without an animated adaptation.
It was not until 2002 that the "Hades arc", the finale to Kurumada's manga, was adapted into an original video animation (OVA) series. The project was divided into three chapters – "Sanctuary", "Inferno" and "Elysion" – spanning a total of 31 episodes. The first chapter was directed by Shigeyasu Yamauchi and scripted by Michiko Yokote. It was broadcast on Animax, a Japanese pay-per-view channel, from November 9, 2002 to April 12, 2003, and later released on DVD in 2003. The second chapter was divided into two parts. The first was directed by Tomoharu Katsumata and scripted by Yosuke Kuroda. The first episodes were released from December 17, 2005, to February 18, 2006. The DVD compilation was released in the same year. The second part of the second chapter was released on Japan's SKY PerfecTV! from December 15, 2006, to March 1, 2007. The third and final chapter was released from March 7 to August 1, 2008.
A group a young warriors known as 'Saints', each in possession of a 'cloth' guarded by a different constellation, must protect the reincarnation of the goddess Athena as she attempts to keep the Earth from being destroyed by evil forces.