Set in the picturesque wilds of a Midwestern resort town at the height of the tourist season, Sister Simon's Murder case begins with the murder of a terrified elderly lady, Dannie Grear. But what was she so afraid of? And who is the killer who keeps attacking anyone he thinks may know too much?

The opinionated local police ran into one obstacle after another in their attempts to find the elusive killer. But the menace was effectively removed by the independent investigation of Sister Simon, a very proper nun who had learned from her policeman father never to take anything for granted in a murder case and how to fire a gun with deadly accuracy. (Summary adapted from the original jacket by Maria Therese)