25 episodes
In the year 2022, a massive online role-playing game called Sword Art Online (SAO) is launched. With the aid of "NerveGear" technology, players can control their avatars within the game using nothing but their own thoughts. Kazuto Kirigaya is among the lucky few who get their hands on the first shipment.
See season 1 details24 episodes
A year after escaping Sword Art Online, Kazuto Kirigaya has been settling back into the real world. However, his peace is short-lived as a new incident occurs in a game called Gun Gale Online, where a player by the name of Death Gun appears to be killing people in the real world by shooting them in-game. Approached by officials to assist in investigating the murders, Kazuto assumes his persona of Kirito once again and logs into Gun Gale Online, intent on stopping the killer.
See season 2 details24 episodes
The Soul Translator is a interface which interacts with the user's Fluctlight—the technological equivalent of a human soul—and fundamentally differs from the orthodox method of sending signals to the brain. The private institute Rath aims to perfect their creation by enlisting the aid of Kazuto Kirigaya. He works there as a part-time employee to test the system's capabilities in realm generated by the Soul Translator.
See season 3 details23 episodes
Despite the defeat of Quinella—the pontifex of the Axiom Church—things have not seemed to calm down yet. Upon contacting the real world, Kazuto "Kirito" Kirigaya finds out that the Ocean Turtle—a mega-float controlled by Rath—was raided. Due to a sudden short-circuit caused by the raiders, Kirito's fluctlight is damaged, leaving him comatose.
See season 4 details