Lovely cyborg Alita and her allies dive into the center of Melchizedek, the super computer that is holding her friend Lou's brain hostage as one of its organic components. There, Alita witnesses a vivid vision of the undead life of her recent battlefield opponent, the mysterious vampire Caerula, who presented her with the key to Melchizedek's kingdom...
Alita enters the massive AI structure Melchizedek with the key given to her by the vampire, Caerula. The narrative, as Alita's vision, takes place 200 years prior. Earth was forced into an ice-age because of a meteor strike, virtually eradicating the human species but for a few. Vampires have survived however, and under the leadership of Victor they feed on the remaining humans.