Nancy plans to take a trip to South America by boat,along with chums George and Bess. They have joined a tour being conducted by an exclusive girls school. A mother of one of the students protests Nancy's presence on the tour. Prior to departure, Nancy learns there are issues involving the Trenton trunk company, mostly concerning the quality of merchandise; the owner, a friend of Carson Drew, asks Nancy to interfere in daughter Doris' life and relationships, so she will marry the son of a former business partner. . . Nancy receives a Trenton trunk to take along on her trip. Nancy has her usual problems as when searching for a case with the initials ND, a case falls, or was it pushed, and hits her on the head and Nancy blacks-out. Nancy comes to some time later, but finds the door to the ro