Petey the Cat has just been released from jail and is trying to start a better life, but things are still complicated between him, Dog Man, and Li’l Petey. At the same time, Li’l Petey is struggling emotionally and trying to understand what “good” really means in the world.
Meanwhile, new villains appear (including a group of psychic tadpoles and the Fair Fairy), and chaos spreads in the city. Dog Man and Petey are forced to put aside their rivalry and work together, because Li’l Petey—and the whole world—needs them to cooperate.