He was invited to breakfast by Lil' Petey and 80-HD, much to Petey's dismay. He said to Petey that he "had a nice place" before proceeding to break the dishes, saying it was Petey's fault they got broken. Later, when his son & grandson left, he took all their belongings and attempted to sell them. He was later caught and taken to jail. Grampa has a ginger striped body with a complete tail, unlike Petey. He has 6 whiskers (he pulled one off in Dog Man: Fetch-22 when he switched places with his son, which he now has 5), a stubble from a shaved beard, and his skin color is slightly darker than Petey, to show his age and distinguish him from his son. He also wears a pair of round glasses. At long last, Dr. Scum discovers a weakness of Dog Man's to exploit, and tailors his latest criminal invention to do just that. His mechanized "Burgle Balls" terrorize the citizenry, stealing a fortune in jewelry and other expensive wares. Dog Man will have to battle his own canine nature to stop Dr. Scum, but he won't have to go it alone. Li'L Petey (aka Cat Kid) and 80-HD (Lightning Dude) are at his side, warriors for justice to aid the "Bark Knight". The Burgle Balls can't overcome all three, but Dr. Scum has a contingency plan: his Colossal-Bot 2000, a four-armed behemoth that could crush the city beneath its feet. Can the Bark Knight, Cat Kid, and Lightning Dude defeat this new foe? Maybe if Petey joins the fight, affirming his commitment to change his ways for the kid's sake. Whether or not Petey's father can be reformed, Petey has the choice from this day forward to set an example for Li'L Petey by opposing his own darker urges. Has he truly turned good? We'll find out as the series moves forward.

The Cupcakemobile and Cupcake Computer are both based on the Batmobile and the Batcomputer, all spoofing Batman's belongings. When the robber throws the ball and Chief's clothes fall off going POW!, this is a reference to the Peanuts comic strip by Charles M. Schulz, when Charlie Brown gets hit by a fly ball on the pitcher's mound. Crunky and Bub make him a cupcake superhero called Commander Cupcake. He somehow then escaped Cat Jail without any trouble and captured all of the FLEAS. Dog Man was created when a cop and his police dog were hurt in an accident. The cop's head was dying and the dog's body was dying, which prompted a nurse to come up with the idea to sew the dog's head onto the cop's body. They did and Dog Man was created. He immediately became an elite crime fighter, the best officer on the police force. The problem is that Dog Man has some of the mannerisms of a dog, which hampers his ability to be effective. He can also be very annoying. Because of that, he is the third most disliked character in Dog Man, behind Li’l Petey and Molly, who are also very annoying especially when they are together because they sing very annoying and unfunny songs in book 10.

At the end of the story, Sarah interviewed Dr Scum about being new. Dr Scum ended the interview after the fourth question due to not being new. It went like this:

Dog Man and Li'l Petey are not looking at them in the original cover, but changed at the last minute. The relationship between Petey and Lil' Petey continues to evolve during the second novel of this set, titled Dog Man: Fetch-22. Petey is now officially one of the good guys and embraces his role as Lil' Petey's dad. Petey's father, known throughout this guide as Grampa, is in jail as this novel opens, having stolen all the stuff from Petey's Secret Laboratory. Lil' Petey has also made an important discovery. The Supa Brain Dots, which were a main part of the story line of a previous novel of this series, actually cause “supa anger.” That explains why Flippy the fish became a villain in a previous novel. Lil' Petey's research prompts Flippy to be released from jail. It's Big Jim's birthday, and the warden gave him a lot of balloons. He gives one to Tippy, Fluffy, and Mr. Whiskers. He tries to give Petey a balloon, but Petey pops it with his claw, making Big Jim cry. Petey tries to make Big Jim happy, but Big Jim tells him to go away. Petey finally makes Big Jim happy when he claims that he got Big Jim a present, which he buried in the jail yard litter box, and will hold Big Jim's balloons while Big Jim digs it up. Unknown to Big Jim, Petey flies away with Big Jim's balloons, and Big Jim only finds poop in the litter box. Recasting Dog Man and his feline ward, Li’l Petey, as costumed superheroes, Pilkey looks East of Eden in this follow-up to Tale of Two Kitties (2017).What do you get from sewing the head of a smart dog onto the body of a tough police officer? A new superhero from the incorrigible creator of Captain Underpants. Petey's dad. He's a selfish, egotistical meanie who currently resides in Cat Jail. Petey and Li’l Petey no longer associate with him. Big Jim is a cat who currently a prisoner at Cat Jail, along with Petey, Mr. Whiskers, Tippy, Fluffy, and several other unnamed cats. When he got hypnotized by Crunky and Bub, he thought he is a superhero named Commander Cupcake, and therefore started an addiction to cupcakes. The following versions of the books were used to create this study guide: Pilkey, Dave, Dog Man: For Whom the Ball Rolls and Dog Man: Fetch-22. Scholastic Inc. New York, New York, 2019. Kindle AZW file. Petey is giving a speech about how cats deserve more rights than dogs, while the FLEAS are forming a new plan on Petey's whisker. He is interrupted by the Jail Warden, telling him he got a pardon. He then forgets everything he just talked about and tries to leave Cat Jail. Big Jim then shows up and gives Petey a hug, and the FLEAS end up on Big Jims whisker.