A circle of energetic young friends spends a summer preparing for and undertaking a motor-boat cruise on a nearby lake. The plot moves episodically through planning and departure, encounters with stowaways, a regatta and race, drifting and peril in a storm, island camping, a suspicious ghost and its eventual capture, and the recovery of missing papers and a saddle. Along the way the characters face fires, mysteries, and practical dangers, relying on cooperation, quick thinking, and outdoor skills. The narrative mixes warm domestic moments with action-driven episodes that highlight teamwork, courage, and resourcefulness.