Ketika sedang menyelidiki SMP Higashi, Ikki dan kawan-kawan mengetahui bahwa tujuh keanehan sekolah berhubungan dengan markas mereka. Tapi, ternyata ada satu keanehan yang tak berhubungan dengan markas itu.
Ketika sedang menyelidiki ke sana, mereka bertemu hantu sungguhan! Setelah dilihat lagi, Ikki menemukan goresan karena A.T dan mau menyelidikinya lebih lanjut. Tapi, mereka ragu karena takut.
Apa yang sebenarnya mereka hadapi, hantu atau pengguna A.T yang ingin menantang mereka?
Oh! great, whose real name is Ito Ōgure (大暮維人 Ōgure Ito) is a Japanese manga artist most recognized for the manga series Tenjho Tenge and Air Gear. In 2006, he received the Kodansha Manga Award for shōnen for Air Gear. Apart from working with manga, he designed some of the alternate character outfits in the PlayStation 2 version of Namco's 3D fighting game Tekken 5, and a guest character in Soul Calibur IV named Ashlotte.
His pseudonym "Oh! great" is a play on words. His pen name, written in Japanese order, is "Ōgure Ito", which is pronounced similarly to and can be romanized the same as the Japanese rendering of the English words "Oh great," ōgurēto. Furthermore, "Oh" can mean "king" in Japanese, making it possible to read the name as "the great king".