A young Milrose State college student goes out early one morning to prepare for his first bicycle race and is abruptly sidetracked when he discovers the body of a young woman, sadistically murdered and nailed to the wall of a pavilion. There had never been a murder in this small Minnesota town and now the first one for the records is a crucifixion.
Recently appointed to detective status, Sally Fairfield receives a phone call from Detective Bob Carpenter of the Milrose Police Department and reports to the scene of her first homicide investigation with a hangover. Assigned to investigate the case, the two detectives quickly realize they're in over their heads. Carpenter, a law enforcement officer for over twenty years, has never worked a murder case. With more than one suspect in the small town, they opt to call their friend, Josh Trimble, from the Minnesota Department of Criminal Apprehension.
An arrest is made, but is this person the murderer? The three detectives have some doubts, but the inexperienced county attorney insists on an indictment. While the detectives review the clues, a trial takes place, and with lives at stake, revelations after the trial break the case wide open in The Janitor Solves a Murder.