After being entrusted with the fate of the world by the Cardinal, Kirito and Eugeo head to the top floor of the Central Cathedral. On the way, they find their confiscated swords among a vast pile of weapons in an arsenal, only to be greeted with a hail of arrows by the Integrity Knight, Deusolbert Synthesis Seven.

Kirito and Eugeo are on their way up the stairs of the Central Cathedral when they encounter two girls named Linel and Fizel. As they stand, wondering what two children are doing there, they let their guard down and...

Though riddled with wounds, Kirito manages to activate his Perfect Weapon Control art. Continuing on their way to the top floor of the Central Cathedral, Kirito and Eugeo find themselves standing before a strange-looking floating platform.

When Kirito and Alice both unleash the Perfect Weapon Control art in the Cloudtop Garden, the impact rips a hole into the seemingly impregnable Central Cathedral wall, which sends them both flying outside.

Eugeo reaches the ninetieth floor of the Central Cathedral, which turns out to be a vast bathing area. The perplexed Eugeo encounters Bercouli Synthesis One soaking in the bath. Meanwhile, Kirito and Alice are still climbing the Central Cathedral wall.

Recap of the first 18 episodes of Alicization.

Seeing Alice’s reaction when he mentioned the name Selka, Kirito decides to tell her the truth about the Integrity Knights. Meanwhile, after being knocked unconscious during his battle with Bercouli, Eugeo awakes on the top floor of the cathedral.

Kirito and Alice reach the communal bath on the nintieth floor. There, they find the Integrity Knight Commander, Bercouli, who's been turned to stone by Chudelkin. Alice breaks down in tears upon seeing her mentor's tragic plight, but then...

Standing in Kirito and Alice's way is Eugeo, who's undergone the Synthesis Ritual and become an Integrity Knight. Kirito is rattled, until Alice admonishes him into resolving to fight Eugeo with everything he's got.

On the top floor of the Central Cathedral, Kirito, Eugeo, and Alice finally face Administrator. But Chudelkin uses the sacred arts to transform himself into a giant clown and attacks.

Cardinal appears on the top floor of Central Cathedral for a showdown with her bitter foe of the last two hundred years. She moves to achieve her objective of deleting Administrator, only to see the fallen sword golem rise up again.

Carrying the hopes of Cardinal, Eugeo, and Alice in his heart, Kirito stands yet again and visualizes the Black Swordsman, the top player who cleared SAO. For the sake of everyone he’s encountered in this world, Kirito, faces off with Administrator.

Recap of Sword Art Online: Alicization, aired one week before Sword Art Online: Alicization - War of Underworld.