After his secret is exposed, Rin takes part in a special mission along Shura and Yukio to retrieve the "Left Eye of the Impure King", a demon relic that was stolen from the True Cross Academy's vault. In the occasion, they fail to retrieve it, but discover that the culprit is Saburota Todo, one of the exorcists in charge of the vault that was corrupted upon being possessed by a demon. After hearing that there was an attempt to steal the Left Eye's sister relic, the "Right Eye of the Impure King" in Kyoto, the Order sends a team there to investigate, including Shura, Yukio and the Exwires, who are in conflict after learning the truth about Rin.

Shiro Fujimoto, Rin and Yukio’s adopted father, encountered Tatsuma Suguro while trying to take the demonic sword, Kurikara. Tatsuma’s letter reveals the circumstances of how the sword, which is the Myoda Sect’s main object of worship, came to Rin.

The Impure King has been revived! In his letter, Tatsuma asks Rin to use the Koma sword to fight, but will that even be possible? And to make matters worse, Mephisto suddenly appears with the news that Rin has been sentenced to death!

“You despise your brother, don’t you?” Yukio is shaken as Todo tells him to admit his true feelings. Yukio reflects on the thoughts he’s had since an early age. Meanwhile, Suguro has inherited the Gouha-en, and with it, he and Rin head to the sporangium.

The sight of a blue flame burning in the night sky is reminiscent of “Blue Night,” but has brought about a completely different result. Now that the incidents relating to the Impure King have been concluded, those affected are moving on.

Bundled with the 19th volume of the Blue Exorcist manga.

Based on the title chapter from the Ao no Exorcist: Spy Game short story collection novel.

Rin Okumura, a boy aiming to become an exorcist yet born the illegitimate son of the demon god Satan, advises his classmate Sei Godaiin, who begins to see demons. Despite Rin asking Ryuji Suguro and the other Exwires attending the Exorcism Cram School for a way to make demons invisible, he is unable to find a solution. Meanwhile, Rin is invited to dinner by Mephisto Pheles, the Preceptor of the Japan Branch of the Knights of the True Cross and director of the True Cross Academy. However...

Yukio Okumura, Rin's younger twin brother and Intermediate Exorcist First Class, is summoned to a high-level inquiry meeting of the True Cross Order to be questioned about Saburota Todo, the mastermind behind the resurrection of the Impure King. Suspicious of the imposing atmosphere, Yukio recalls the words of his late adoptive father, Shiro Fujimoto. Meanwhile, the Exwires are tasked with exorcising "Mayuko of the Toilet." However, Izumo Kamiki holds a certain grudge against Shiemi Moriyama.

True Cross Academy is busy with preparations for the school festival. Renzo Shima and Rin try to find partners to attend the music festival and dance party with, but they are continually rejected. Unwilling to give up, Rin attempts to invite Izumo. But she flat out declines because the annual Exorcist Certification Exam is approaching. However, Shiemi, who has passed the school's transfer exam and has become their classmate, appears before a completely depressed Shima and Rin.

Arthur A. Angel and Lightning capture a spy hiding among the Knights of the True Cross and learn that the secret society, the Illuminati, is planning to abduct someone for a certain project. And now, the time for their plan is at hand. After hearing the news, Shura Kirigakure gathers the Exwires. Meanwhile, Izumo confronts Takara and angrily explodes when she sees a particular stuffed animal in his hands...