Blue Exorcist -The Blue Night Saga-

Sequel to Ao no Exorcist: Shimane Illuminati-hen. Uncover the dark side of the Knights of the True Cross and the mystery of the "Blue Night"! Brothers Rin and Yukio head to Lake Towada in Aomori to search for Shura, who had suddenly disappeared. There, they find Shura’s birthplace – the place where Shiro became her guardian. As their search continues, Rin and Yukio discover the fate that awaits Shura. Meanwhile, Lightning, one of the Arch Knights, arrives at the Japan Branch of the Knights of the True Cross and begins his investigation into the Illuminati. Lightning deduces that everything began on the “Blue Night,” as he gradually steps into the dark side of the Knights of the True Cross….

In the late Edo Period, a demon known as the Impure King killed thousands of people. After defeating the demon, the Knights of the True Cross kept its left eye safely sealed away on Academy grounds - but now someone has stolen it! Hearing the thief has taken a child hostage, Yukio and Rin go to help. The investigation and pursuit will lead Rin and his friends to Kyoto and involve them even deeper in a sinister plot! But will his friends' knowledge that Rin is the son of Satan drive a wedge between them?

This world consists of two dimensions joined as one, like a mirror. The first is the world in which the humans live, Assiah. The other is the world of demons, Gehenna. Ordinarily, travel between the two, and indeed any kind of contact between the two, is impossible. However the demons can pass over into this world by possessing anything that exist within it. Satan the god of demons, but there's one thing that he doesn't have, and that's a substance in the human world that is powerful enough to contain him!! For that purpose he created Rin, his son from a human woman, but will his son agree to his plans? Or will he become something else...? An exorcist?

New TV anime series of Ao no Exorcist . At True Cross Academy, Rin Okumura unknowingly comes across the first signs that something is amiss; ordinary people have been gaining the ability to perceive the invisible creatures that roam the human realm, Assiah. While Rin sees this as an opportunity to make a new friend, his twin brother, Yukio, is more burdened than ever. Swamped with his education, exorcist duties, and teaching position, Yukio has remained silent about his awakened powers, unable to understand their scale or significance. While Rin and his friends prepare for the annual Exorcist Certification Exam, the True Cross Order has uncovered the first artificial gate to the demonic realm of Gehenna. Witnessing its size and the advanced technology that made it possible, the exorcists realize they are now dealing with the Illuminati, an extremely wealthy and powerful organization. Moreover, the inscrutable Illuminati have planted three spies in the True Cross Order—and one may be hiding among the aspiring exorcists sworn to protect mankind from the demonic threat.