Now a driver in the chariot races, Nic is still a target of the Praetors because of the magical amulet he found, and they will do anything to get their hands on it--and meanwhile Atroxia is beginning to wake up.

"After the tragic death of their father, Emily and Navin move with their mother to the home of her deceased great-grandfather, but the strange house proves to be dangerous. Before long, a sinister creature lures the kids' mom through a door in the basement. Em and Navin, desperate not to lose her, follow her into an underground world inhabited by demons, robots, and talking animals. Eventually, they enlist the help of a small mechanical rabbit named...