A priest approaches an elderly couple praying in church and finds bullet holes in their skulls. A jogger killed along the river has a bullet hole above his brow. A strangled prostitute is discovered draped over a cemetery stone angel.

Grace MacBride, head of a software company in Minneapolis, sees the news photograph of the cemetery murder and recognizes its similarity to a picture in the game her company, Monkeewrench, is developing. The Serial Killer Detective game is still in its testing phase, but Monkeewrench put a test version with the first seven murder scenes on its website to track the strategies of the players. Who, of the 587 registered users and the members of Monkeewrench, is duplicating the murders in real life? MacBride calls the Minneapolis homicide department and brings Detective Magozzi into the loop.

Magozzi notes what an oddball bunch makes up Monkeewrench. They have hidden their histories as though they are in the witness protection program. The FBI shows undue interest in the fingerprints that Magozzi knows come from Grace MacBride, but Magozzi is sure she is not the serial killer. She and her cohorts are armed, living in fortresses, afraid of something or someone. While the Minneapolis police organize to prevent the murders that copycat the game, Magozzi tries to get to the bottom of the mystery of Monkeewrench.

This remarkable first thriller from P. J. Tracy, combining humor, good-heartedness, and breathtaking suspense, raises the bar to which other writers must aspire.