No matter the season, the Philadelphia private school where Amanda Pepper teaches English is never a center of tranquility. But with Halloween and the annual Mischief Night party only days away, the hope is that nothing more than old-fashioned vandalism and pranks will take place.

No such luck. Trouble erupts long before the witching hour, as the school is plagued by a series of mishaps ranging from the trivial to the potentially deadly–and most of which seem to center on a group of popular seniors.

A fire alarm rings during a test; all the orange and black paint is stolen from the art room; the mustard packets are taken from the cafeteria. Perhaps more serious: chemicals and equipment disappear from the science lab, as does one of Amanda's exams and her attendance book. And the dapper new science instructor, Juan Reyes, receives a threatening message recalling that a teacher was once flayed to death by his students.

As Amanda juggles teaching, moonlighting as a private investigator with her husband, C.K. Mackenzie, and coping with C.K.'s visiting sixteen-year-old high school-dropout nephew, she tries to find out what, or who, is behind the ominous events.

Before she can unmask the tricksters, the turmoil in the school increases when students rise up against the administration's censuring (and censoring) of a campus poet. Then unrest escalates into a lethally explosive menace, and Amanda receives a warning that there is more–and far worse–to come.