The story of the first season follows the adventures of Kazuto "Kirito" Kirigaya and Asuna Yuuki, two players who are trapped in the virtual world of "Sword Art Online" (SAO).

[2][3] Three months after the death game, Kazuto discovers that Asuna is being held captive in "Alfheim Online" (ALO), a spiritual successor to SAO, where the players assume the roles of fairies.

Kazuto enters the game and allies himself with his sister Suguha "Leafa" Kirigaya to rescue Asuna from captivity.

[5] Aniplex of America announced that the English dubbed version would air on Adult Swim's Toonami programming block starting on July 28, 2013.

Sword Art Online: Extra Edition is a special anime episode which was simulcast worldwide on December 31, 2013.

[57] The extra edition was directed by Tomohiko Itō and screenplayed by the creator, Reki Kawahara, and Munemasa Nakamoto.

[58] It recounts the events of the original Sword Art Online anime, told in retrospect by the series characters and features new footage.

[61] Sword Art Offline is a series of bonus episodes released in their own DVD and Blu-ray volumes in Japan.