The 32nd Knight
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.
Aired 10/03/2019EP 21 - The 32nd Knight
Sword Art Online: Alicization
Kirito awakens in a vast, fantastical forest filled with towering trees. In his search for clues to the truth of his surroundings, he encounters a young boy who seems to know him. He ought to be a simple NPC, but the depth of his emotions seem no different than a human. As they search for the boy's parents, Kirito finds a peculiar memory returning to him. A memory from his own childhood, of this boy and a girl, too, with golden hair, and a name he should have never forgotten - Alice.
(Source: Yen Press)
Note: The first episode aired with a runtime of ~48 minutes as opposed to the standard 24 minute long episode.