Bayport is hosting its first Grand Prix race, and former world-champion driver Angus McCoy is on hand. But during his qualifying run, McCoy misses a hairpin turn, and his car plunges into the bay. When Frank and Joe try to help investigate, they are beset by violent "accidents," including the destruction of a vital clue. The brother detectives find themselves trapped in a deadly duel of fast cars and freewheeling danger as they chase down the missing link to a murderer. If the Hardys fail to win the rat race, they'll finish in a dead heat with the grim reaper.