Superintendent of Middlefield Schools, Colin Winslow, suffers an allergic reaction while driving home from a school board meeting. He uses an epinephrine injector device he is testing for his inventor friend, John Burns, but to no avail. Winslow collapses and dies as his car smashes the railroad crossing gates and collides with a train.
New York detective Rick Canyon is rousted out of bed by Roger Greenfield to go to the accident scene at the request of Winslow's wife, Alex.
Coroner Bill Crandell's autopsy shows that chocolate milk Winslow had been drinking was laced with penicillin, to which Winslow was highly allergic.
Glen Abner, the school district's treasurer, is arrested. He gave Winslow the milk. His motive: Winslow accused him of embezzling school funds, which Abner admitted to but did not want such degrading and embarrassing information to become public and destroy his career.
Canyon discovers that a paranoid Winslow had secretly taped all his conversations with school officials. Canyon's pregnant wife, Maddie, uses technology supplied by computer expert, Dan Hennigan, to decode the tapes to create a list of murder suspects. Canyon discovers Winslow's tell-all memoirs of twisted dealings from various school systems in which he had previously served as superintendent that ultimately revealed additional suspicious characters.