When Adriana Chambers observes a stranded motorist struggling to change his tire, she sees in his distress an opportunity to be a good Samaritan. Pulling over, she offers her help—but she gets much more than the satisfaction of serving. As the beautiful young college student finds herself the only witness to the man's whereabouts that morning, she is unwittingly drawn into a criminal investigation that tests her powers of deduction. The stranded motorist, Jerzy Grabowski, has been charged with murder. The complication: he's innocent.