When a chocolate turkey--the intended prize for the winners of a Thanksgiving Day race--disappears, Nancy and her friends identify and eliminate suspects in their search for the missing confection.
Nancy Drew and her friends become caught up in a dangerous investigation when they agree to help search for a diamond thief while on a cruise around the Great Lakes.
To celebrate her birthday, George is taking Nancy and Bess on a bike tour around Mystic Lake, but when their tour guide disappears and unknown adversaries steal their supplies and slash their tires, Nancy begins looking for clues.