When leatherback turtles start washing up on Nova Scotia's South Shore, thirteen-year-old Will is alarmed. The deaths seem to be the result of loud underwater explosions Will has been hearing--but who and what are causing these explosions? Could there be a connection to the local shipwreckers who endanger lives in their reckless efforts to plunder disabled boats? Theories abound, but no one can solve the problem, not even his cousin Harley, because she's too busy at the sail shop. So Will takes it upon himself to investigate.