Dorothy and her schoolmates return to their mountain boarding school and encounter a new, stylish pupil whose presence sparks jealousies and pranks. Rivalries escalate through everyday episodes—running races, a student-run lunch counter, and a dangerous canoe upset—while mishaps accumulate: a girl trapped in a bog, a stolen picture, a roadside robbery and other perplexing incidents. The girls respond with teamwork, resourcefulness, and investigative efforts that involve teachers and trustees. The book interweaves friendship, school politics, and youthful courage as tensions build to a formal inquiry and a decisive meeting to settle disputes.