Set at the elite Cross Academy, the story follows Yuki Cross and Zero Kiryu as the 'Guardians' of the school, tasked with maintaining order between the human Day Class and the aristocratic vampire Night Class. Yuki holds no memory of her past before being attacked by a vampire ten years prior, when she was rescued by Kaname Kuran, a pureblood vampire and leader of the Night Class. As hidden conspiracies unravel, Yuki discovers shocking truths about her own identity and her deep ties to the vampire world, while Zero battles a dark secret of his own.