It is summer and Dune House is gearing up for the tourist season. Suzie and Mary are looking forward to welcoming new guests who are being flown in on a seaplane specially organized for tourists during the summer months. But when the pilot is murdered, and a lost dog is found, Suzie and Mary find themselves trying to solve not one mystery but two. Their investigations uncover a web of lies and land them right in the line of fire. It is a race against the clock to solve the murder before the suspects fly away.