Helen, Margy, and Rose settle back into their daily life in the city, but not without more problems. Rex Pepper continues to attempt to steal Miss Pepper's fortune, and Helen may have lost her only source of income after Mr. Bullard is swindled in a stock scam. Margy discovers that Rex Pepper is part of the ring of stock swindlers and enthusiastically agrees to go undercover in order to gather evidence against Rex Pepper and his cronies. Margy journeys to the Royce Clever-Carlton estate in disguise and plunges into a dangerous situation that nearly backfires on her. Ultimately, Margy is triumphant, but not until after she suffers through several dangerous experiences.