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 fifth-grader Nathan Abercrombie, a half-dead zombie whose body cannot heal itself, is approached by messengers from the Bureau of Useful Misadventures (B.U.M.) and offered the chance for a cure if he will become a spy, he doesn't realize that B.U.M. is not exactly trustworthy.
Nathan's career as a half-dead zombie spy may be over just as his training has begun when he and friends Abigail and Mookie enter East Craven's sewers to investigate the greasy green goop dripping from every faucet in town.
A mold problem disrupts things at Nathan's school and his class is forced to share a space with first and eighth graders including Rodney the bully's older brother. Meanwhile, Nathan notices that a putrid smell is following him around and tries to discover its source.