After race car driver Kiki Cutter is injured during a race, Mark, knowing her from his own racing days, decides to pay her a visit. Fortunately for Kiki, Mark arrives just as someone tries to kill her. Although the killer manages to escape, Mark does manage to get his license plate number. Believing that the attempted assassination may be tied into Kiki's crash, Mark sneaks a look at the car. Confirming his suspicions, Mark finds evidence that Kiki's car was sabotaged. Meanwhile, Hardcastle traces the assassin's license plate to Hal Jenkins, an insurance broker. Some of the pieces of the puzzle are tied together when a recovering Kiki reveals that she has been secretly planning on divorcing Sammy "Sidewinder" O'Connell, her race driver husband. Once, Hardcastle has stopped Jake Thomas, the man who tried to kill Kiki, as well as arrested Jenkins, Mark, with some financial backing from the judge, decides to challenge O'Connell in a major car race. Thanks to his superior driving skills, Mark defeats O'Connell and settles a longstanding rivalry between them. Afterwards, O'Connell, who had selfishly acted out of fear of how the divorce would impact his career, is arrested for his part in the attempts on his wife's life.
