Leo Langley uses his crab-finding skills to help cousin Marcus locate a crab swarm, but is betrayed and his profit share withheld. He builds a powerful crab detector and joins Uncle Stone on his boat. He pinpoints deep-sea crab swarms, lands massive hauls, and puts greedy cousin Marcus in his place. Leo Langley then sails the deep seas, embarking on a journey of deep-sea crab hunting.
