In The Rat King, the story picks up where Cat City left off. Susan has been having bad dreams, and without Tucker there to comfort her, she fears something terrible has happened. Tucker has been ordered to stay in Cat City and fulfill his duty as a gatekeeper, but it feels like the council is trying to keep him from his friend. Susan's nightmares turn out to be real, and when Tucker discovers that Susan has been kidnapped by their enemies, he tries to rally help from the cats. But if anyone is going to save her, it's going to have to be him! With the Rat King ready to attack and an old...