George and Harold create a new comic book hero in Dog Man, a crimefighter with the head of a police dog and the body of a policeman, who faces off against his archnemesis Petey the cat.

Dog Man, the newest hero from the creator of Captain Underpants, is still learning a few tricks of the trade. If only the Chief would throw him a bone every once and a while...Dog Man needs to dry up the drool, dust away the dander, and roll out of the refuse if he's going to impress the Chief, and he needs to do it fast! Petey the cat is out of the bag, and his criminal curiosity is taking the city by storm. Can the canine crime biter unleash justice...

When a new sitter arrives and a movie star goes missing, Dog Man and Cat Kid investigate, but Petey, the world's most evil cat, complicates their case.

Petey the Cat is out of jail, and he has a brand-new lease on life. While Petey's reevaluated what matters most, Li'l Petey is struggling to find the good in the world. Can Petey and Dog Man stop fighting like cats and dogs long enough to put their paws together and work as a team? They need each other now more than ever -- Li'l Petey (and the world) is counting on them!

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?