Dog Man: Grime and Punishment (2020) is the ninth installment of Dav Pilkey’s middle-grade graphic Dog Man series. There are currently 11 Dog Man books. The Dog Man series is a spin-off of Pilkey’s extremely popular Captain Underpants series, which comprises 12 novels.

Plot Summary

George and Harold, fourth-grade best friends, set up a stall in a local mall to sell the latest installment of their comic book, Dog Man. It becomes wildly popular; long queues form of people wanting to buy the comic. In following chapters, the reader understands that they are reading George and Harold’s Dog Man creation, which details the following:

Dog Man is half man, half dog; he works as a cop in the local police department. Dog Man was created when a police dog’s body was irreparably damaged in an explosion, as well as a policeman’s head; doctors managed to stitch the dog’s head onto the man’s body.

The Police Chief (called “Chief”) is being presented with an award at a ceremony in City Hall hosted by the mayor (called “Mayor”). Dog Man is supposed to be there to present the award; he is late because he was digging up Mayor’s rose bushes—much to Mayor’s chagrin. Dog Man arrives late and covered in mud, steals Mayor’s hat, and causes the building to collapse. Mayor fires Dog Man and takes his police badges. He will not budge on his decision even when Chief and Dog Man go to Mayor’s home to beg him to give Dog Man his job back.

Li’l Petey, a cat with human qualities, and a robot, 80-HD, comfort Dog Man and come up with an invention to help him to get his job back: a hat that disguises Dog Man as a cat, complete with ears that “meow” and “hiss” when tweaked. Dog Man goes to the police station. The building is flooded with Chief’s tears; he is crying over a photo of Dog Man. Dog Man arrives; Chief is thrilled to see him. Mayor arrives and is convinced by Dog Man’s disguise. He hires Dog Man (believing that he is a cat).

Meanwhile, Li’l Petey’s grandfather, Grampa—also a cat and long-standing criminal—is developing an invention while in prison: the Motor Brain, which accentuates the personality of whoever is wearing it. When Big Jim, one of Grampa’s grandsons, puts it on, he becomes the extremely loving Snug. Grampa puts it on and becomes the violent Crud. Grampa, as Crud, escapes from prison.

Petey is Li’l Petey’s father and creator. Petey is also a cat with human qualities, and he cloned Li’l Petey. Li’l Petey asks Petey why he hates Grampa so much. Petey explains that Grampa is a villain. He also explains that Grampa was cruel to Petey’s mother, Gramma, and that Grampa abandoned Petey and Gramma. Petey is shocked that Li’l Petey doesn’t hate Grampa; Grampa had previously kidnapped Li’l Petey. Li’l Petey explains that he has chosen to forgive Grampa. Petey maintains that hating Grampa is the only way to live.

Dog Man, disguised as Cat Man, confronts Crud in the street. Mayor, watching television coverage of the events from home, realizes that Cat Man is in fact Dog Man and rushes to arrest Dog Man and all of the cops, including Chief, who were aiding Dog Man. This allows Crud free range of the city; he continues to violently rampage. Crud brings a giant lunch bag to life. The lunch bag, Munchy, begins to roam around the city, also causing destruction.

Eventually, Munchy reaches a pond. He seizes Flippy, an adult fish who was teaching a grammar lesson to a collection of the pond’s youths. Petey and Li’l Petey arrive. Li’l Petey and his friend, Molly, decide to vanquish Munchy with love. They love to draw, and they draw their favorite things on Munchy. This causes Munchy to drop Flippy in surprise. The other children draw on Munchy. Munchy decides that he loves his new tattoos and agrees to come to the children’s Comic Book Club meeting. He leaves, happily.

Petey confronts Grampa, who is in the form of Crud. Inspired by his Li’l Petey’s policy of love and forgiveness, Petey decides to forgive his father. Crud, angry and mystified that Petey won’t participate in their usual dynamic of resentful fighting, takes off his Motor Head and returns to the smaller form of Grampa. Looking peaceful, Petey picks up Li’l Petey and returns home.

Big Jim finds the Motor Head and puts it on. He returns to the overly loving form of Snug and chases Grampa, wanting to hug him. Mayor forgives Dog Man after Dog Man saves Mayor and Mayor’s beloved teddy bear, Mr. Snookums, from a house fire. Petey takes Li’l Petey to Gramma’s grave. They reflect that Gramma is a part of them both. Petey feels happy and at peace that he has chosen to finally let go of the hatred he held for Grampa.