A revolutionary VR headset called the NerveGear allows players to fully immerse themselves in virtual worlds by connecting directly to their nervous systems. Thousands of players log into Sword Art Online on launch day and find themselves trapped inside the game. The game world is Aincrad, a colossal floating steel castle consisting of 100 floors, each with different environments, monsters, towns, and dungeons. To escape, players must clear all 100 floors and defeat the boss on each level. The catch: if a player dies in the game, they die in real life. The creator of the game, Akihiko Kayaba, has disabled all logout functions and made survival the only way out. Create your own character and survive.