|Spoiler warning: Plot or ending details follow.|
Academy:Isolation is the thirteenth episode of the Guilty Crown anime. It first aired on January 20, 2012.
Two weeks since the outbreak, the GHQ continues their search and rescue for survivors in Tokyo and helping the citizens. Due to a large number of teenage refugees, most of them are sent to Tennouzu High which has been set up as a shelter. Unable to find the rest of the Undertakers, Shu, Inori, Tsugumi and Ayase stay at Tennouzu High. However, Ayase is mourning over Gai's death and blames Shu and Tsugumi from preventing her to join and die helping him.
Due to tensions among the teenage refugees, the Student Council decides to hold a school festival to cheer them up. At the same time, Shu learns his powers have evolved and can now extract people's Voids while they are still awake. Meanwhile, Segai has taken over the Anti Bodies and sends Daryl undercover to spy at Tennouzu High. As the students prepare the festival, a group of disgruntled refugees see this and decides to attack the school with a Humvee and Endlave provided by Segai.
With the festival going well, Inori is about to go on stage to sing until the disgruntle refugees attack. Shu tries bring Ayase to safety but Ayase scolds him for treating her with pity. Because she can't walk, Ayase is angry that she can only ride Endlaves and can't do nothing else to help everyone now that her Endlave is gone and ask Shu for his help. Shu does so and extract her Void, a pair of leg braces that allow her to rollerblade fast and jump and float high, which both she and Shu stop the disgruntle refugees.
With the troubles over, Inori sings to the crowd while Souta manages to get a TV signal and connects it to the stage TV screen. Much to Shu and everyone shock, Shuichiro is revealed to alive and has become the new President of the Japanese provincial government and has order the area where Tennouzu High is located sealed off.