As the fall semester ends and kids head home for winter break, Jed and his parents gather for the annual exchanging of gift lists. Once again, Jed asks for a dog, leading to a heated argument and a firm "no." But when Jed spots a stray, he chases it until the dog darts into the street where it is struck and killed by a car. Grief stricken by what he's done, Jed cradles the dead dog in his arms. Soon, ooze from the dog mixes with teardrops from Jed, creating Tread the zombie dog. Finally getting his wish, Jed must convince his parents to let him keep the undead dog. But a zombie dog turns out to be the least of Jed's issues. It seems some parents don't want Jed attending school with their kids. Enter the mysterious NZN Network. They've been distributing anti-zombie propaganda in an effort to get Jed expelled. But Jed wonders if the creation of Tread has caused his relationship with Luke to sour. And why, just as he seems to need them the most, have his best friends abandoned him? Could they have bought in to the anti-zombie way of thinking? Was creating Tread a mistake Jed will live to regret? When Tread goes missing, and with his very existence at stake, Jed must rely on his instincts, team up with an old nemesis, and fight for his right to have just as miserable a middle school existence as any other student—undead or alive.