Tired of continually having his feelings hurt by popular students and bullies, fifth-grader Nathan agrees to try an experimental formula, Hurt-Be-Gone, and becomes a half-dead zombie, a condition which, he soon discovers, has some real advantages.

When the head of the Bureau of Useful Misadventures (or BUM) discovers that an evil organization is using the Student Mind and Body competition to recruit agents, he asks Nathan to enter the competition, but things go terribly wrong when Nathan's nemesis starts to notice some odd things about him, and Nathan fears his zombie identity will be exposed.