The paths of one evil god, two rival empires, three unlikely bishops and seven brave ghosts converge in the destiny of Teito Klein, a boy who vows to master a powerful artifact known as the Eye of Mikael in order to lay bare the secrets of the world's - and his own - murky past.

Realizing that to move forward he must understand the past, Teito heads to the Land of Seele with Frau. On the way, Teito takes a journey both into his own past and the tragic history of one of his protectors - Castor, the kind puppet master of the Barsburg Church and one of the Seven Ghosts.