Nine-year-old friends Mellie and Danny rescue a bedraggled cat they find hiding in a trash barrel. They don't realize that he has just made his escape from a nefarious animal-testing laboratory run by the Trump-like CEO of YummCo., the largest employer in town. Mellie names the cat Bert, but Danny calls him ZomBert because of his habit of eating only the heads of his prey. Meanwhile, the lab is pulling out all the stops to find the missing cat. Why is he so important? Is Bert really a zombie? Can Mellie and Danny protect him? Readers will have to wait for the next series entry to find out; this one ends in a cliffhanger. Frequent digital sketches add suspense to a story with dead-on appeal for Halloween reading.

There's something strange about Mellie's foundling cat…is Bert a zombie?!Nine-year-old Mellie has no interest in being a part of her parents' food-and-family blog. Her mother and father (a former freelance writer and former chef, respectively) are so busy with the blog and her twin younger brothers that she's pretty free-range. She spends a lot of her time helping her best friend, Danny, make horror movies. When the two of them discover a disheveled cat in a dumpster, Mellie feels drawn to the sickly feline; she sneaks him home, names him Bert, and doesn't tell her parents. Meanwhile the Big Boss of a local lab is not pleased that two of his workers have allowed test subject Y-91 to escape, and he orders them to find it. Bert isn't interested in cat food or even salmon, but he brings Mellie headless animal corpses…could he be a zombie eating only the animals' brains?! When Bert's accused of hurting the school bully's pet rats (and thus brought to the attention of Mellie's parents), she may not be able to keep him. This slim series opener feels like the start of a novel more than a whole book, as so much is left unresolved at the close. The parallel stories of Mellie's discovery of Bert, the search for Y-91, and Bert, as he pursues a mission of his own, will keep young fans of the slightly spooky turning pages…and eager for the next installment. In Andrews' illustrations, Mellie and her mom have dark skin while her dad and the twins have light skin.Enjoyably mysterious. (Science fiction. 7-10)