Two years have gone by since Kirito and Eugeo left Rulid Village. In the capital city, Centoria, both boys have attained their goal of being admitted to the North Centoria Imperial Swordcraft Academy.

Kirito finds himself in a duel against the Elite Disciple Volo Levantein, using real swords. As the curious crowd looks on, Kirito is encouraged by Sortiliena, and the duel begins.

Asuna has logged into the Underworld using the superuser account of Stacia, the Goddess of Creation. After she descends, she is reunited with Kirito, thanks to Ronie and Tiese. But soon Alice arrives, leading to a precarious situation!

Due to Gabriel's scheme, U.S. players were given black knight accounts, and are now continuously logging in to the Underworld. They begin mercilessly slaughtering soldiers from both the Human Empire Army and the Dark Territory Army.

Sinon has logged in with the super-account of Solus, the Sun Goddess and rescues Asuna and the others at the last minute. Meanwhile, Leafa logs in with the super-account of Terraria, the Earth Goddess, and descends to the Underworld.

The traitor inside Rath turns out to be a researcher named Yanai. When Higa attempts to restore Kirito, Yanai tries to thwart the operation by holding him at gunpoint. Meanwhile, in the Underworld, Sinon confronts Gabriel, who has logged back in.

Sinon manages to severely damage Gabriel, but her strength has been sapped. Leafa collapses after wiping out the American players. And Asuna, her situation now hopeless, gazes at Kirito. But the Black Swordsman continues to wander through his dreams.

Escaping his nightmares, Kirito regains consciousness at last. With the Night-Sky Blade in his right hand and the broken Blue Rose Sword in his left, he faces off against Vassago, armed with the Mate-Chopper, now enormous in size.