Dog Man is down on his luck, Petey confronts his not so purr-fect past, and Grampa is up to no good. The world is spinning out of control as new villains spill into town. Everything seems dark and full of despair. But hope is not lost. Can the incredible power of love save the day?

Dog Man, the newest hero from the creator of Captain Underpants, hasn't always been a paws-itive addition to the police force. While he can muzzle miscreants, he tends to leave a slick of slobber in his wake! This time, Petey the cat's dragged in a tiny bit of trouble-- a double in the form of a super-cute kitten. Dog Man will have to work twice as hard to bust these furballs and remain top dog!

Dog Man has been working hard to overcome his bad habits, but when his obsessions turn to fears, he finds himself the target of an all-new supervillain, while Petey the Cat, who was just released from jail, starts a new life with Li'l Petey.