While helping her best friend, Danny, film his latest horror flick, Mellie discovers a scraggly cat behind a dumpster outside the YummCo Foods factory. Mellie names the stray Bert and hides him in her room, knowing her parents won't let her keep him. But soon Bert has decapitated all her stuffed animals, and before long he is leaving the headless corpses of birds and mice as gifts for her. Danny is convinced the cat is a zombie, living on the brains...

"A thrilling finale to an arch mystery-adventure series pits Bert the cat against the infamous YummCo Labs. Bert was a bedraggled stray before nine-year-old Mellie Gore adopted him-and has already escaped from YummCo once, vowing to find a way back to free the other captives. Now the Yumms have nabbed Bert again, and he wants revenge. Mellie's plans to rescue her pet are interrupted when the entire town, including her own parents, begin turning into...