Kate and Elizabeth connect in San Antonio, Texas, and participate in mission activities and performances at the Fiesta Noche Del Rio on the Riverwalk. During one of their presentations, a tourist boat runs amok and wrecks into the performance platform—frightening the kids, tourists, and the boat tour guide. The girls quickly pick up on rumors that this boating company has encountered a recent string of unfortunate incidents. . .and suspect that foul play is afoot. Will Kate and Elizabeth, with help from the Camp Club Girls, uncover the source of the trouble before the River City Cruise Boat business goes bust?