In Chicago, the host of a controversial radio talk show Sam Kraus is assassinated in the garage of his building by the terrorist group Z.O.G. FBI agent Catherine Phillips is assigned to work undercover in a rural area to investigate the prime suspect Gary Simmons using the identity of Katie Weaver. Katie meets the family man and widower Gary, his mother, his son and his daughter, and she believes he is innocent and they fall in love with each other. Gary trusts Katie, proposes to her and discloses the truth about his bigot friends and himself. Katie faces a this dilemma and asks her superior Mike Carnes to take her off the case. Mike insists she stay on the case and Katie is divided by her love and her duty, leading to a tragic consequence.