Carson Drew's arrest on bribery charges shocks the town of River Htights. Aided by investigative reporter Ann Granger, Nancy swings into action to clear her father. Her main suspect is Carson Drew's accuser- and former best friend- Judge Jonathan Renk.
But before the judge can reveal the truth, he's shot down- and every clue leads to the Gold Star Company. To dig up the missing link Nancy goes undercover as a cabbie on the midnight shift. Once in the driver's seat, however, she finds herself in a deadly demolition derby with a vicious mobster- fighting desperatly to save her life!