With the help of Porta Nova, Alita's finally made it to the Incubator, and is moments away from retrieving Lou's brain, when Super Nova, a new, sinister incarnation of the professor created by Mbadi, steps in and holds all 20,000 brains in the Incubator hostage! Can Alita find a way out? Will Melchizadek be destroyed? And just how many Novas are there?