Mourning his father, lost at sea a year ago, Ben, 12, wants no one to surpass Dad's record in Martha's Vineyard's annual Striped Bass Derby--unless he docs it himself. Out angling for a whopper on the contest's opening day, Ben overhears two men plotting to win the $10,000 prize for breaking the record with a fish caught days ago, weighted with mercury. With the help of better members of the community, who trust his story, Ben is instrumental in averting this threat; meanwhile, his mother realizes that Ben needs the freedom to follow his father as a commercial fisherman despite her anxieties, while Ben gains respect for her new friend Barry after Barry's quick thinking leads to hard evidence backing Ben's accusation. It's all a little too neat, especially when Ben actually does hook a record-breaking fish--and then lets it go: he's finally come to understand his dad's feeling that such a beautiful giant should be left free, ""just swimming and spawning and growing old."" Predictable but wholesome, then, with characters of some depth and individuality and a worthy environmental message about an overfished species.