A group of Camp Fire girls spend a summer at a lakeside camp, organizing meetings, practicing outdoor skills, and enjoying routine camp life until a series of small mysteries and schemes disturbs their peace. They contend with rivalries, meddlesome adults, a suspicious stranger, pranks, and a runaway, and respond with careful planning, watches, and improvised devices to investigate and defend their camp. The narrative emphasizes teamwork, resourcefulness, and steady persistence as the girls uncover deceptive plots, outmaneuver opponents, and safeguard their honor and friendships by the season's end.