The Altair and Garuda successfully infiltrate the Gards-orm base after fighting Abyss and Sin, only to enter the Gards-orm's quantum computer and be confronted by Naga and his views on the nature of life and humanity.
Ryoko's data is repaired thanks to Sin's data transplant, but her emotional data component is locked within the Altair so she is seemingly emotionless in the server. She and Kyo explore the real world, where he affirms that while he and Ryoko are only apparitions, they will some day be able to touch the real world.
The Maihama server resets and the summer school term starts again; Ryoko returns to the server, but is hospitalized and comatose. Kyo discovers that Ryoko can only exist as herself within the Altair, which causes pain for them as well as those around them.
Things seem to be going right for Kyo - Ryoko will come back, he's finally made up with Kawaguchi, and his friends are happy. But the world itself is acting strange and Kyo finally discovers the server can only simulate a limited time period before resetting itself.
Kyo must overcome his grief over Ryoko's loss while Lu Sheng reveals what caused humanity to be stored within servers in the first place. Shizuno desperately searches through the raw combat data of the Altair and finds Ryoko's data compressed in the mecha's memory.
The crew of the Oceanus survey potential Celebrant candidates, which include Ryoko, Hayase, and Tomigai. Ryoko fully awakens and she spends the day with Kyo and asks to see the real world someday with him.
Arque spends her last days making lasting memories with Chris, Kyo, Shizuno, and Ryoko. Sin and Abyss return and Ryoko begins to "awaken".
Ryoko uses a video tape from Tōru Kanō to create a new film, not realizing that it is a sign she may "awaken" to the real world soon. She and Kyo make up during the Summer Festival.
Memories that Kyo does not recall and off-hand comments from his comrades hint that Kyo's past is more complex than he realizes. Accompanied by May-Yu, he goes to see the real Maihama so he will experience the pain of reality and know why he must continue to protect his illusory world.
Finally convinced that Maihama is an artificial illusion, including those cares most about, Kyo spends the day with Ryoko at the aquarium, who notices he has changed despite how he acts otherwise.
May-Yu, May-Yen, and Lu Sheng are determined to save the corrupted Shanghai Server with help from Kyo and Shizuno. When the server is destroyed, Kyo discovers the truth behind what is reality and what is a dream.
As Kyo plays a game given to him by Student Council President Shima, he begins to question the reality he lives in.