The mind behind the redoubtable Captain Underpants teams up with a new illustrator for a new series, featuring a pipsqueak mouse and his humongous metal friend. Enraged when his new robot refuses to destroy nearby Squeakyville, mad doctor Stinky McNasty turns a classroom lizard into a monster with a drop of Hate Potion #9. In the meantime, the robot, having bonded with little Ricky, intimidated the bullies who threw his backpack in the garbage, and taken up residence in his garage, lumbers into battle, saving the day in a flurry of reader-animated “Flip-O-Rama” scenes. In thick-lined cartoons, the hamfisted robot looks like Popeye in sheet metal; the bad guys all have squinty eyes; the fight is all. Children younger than the Captain’s readership may find this droll, but Pilkey’s just treading water; so rudimentary is the plot, so stock the characters, and so free is this of humor, that it may sink like the proverbial lead balloon. (Fiction. 7-9)