Two US government agents, Hal Duncan and Sam Bradley, must prevent agents of a foreign power, led by Regan and Cady, from hijacking trucks and stealing defence materials being transported by truck. They are hired by an interstate trucking association whose constituent truck lines have been principal targets of the hijacking, and it becomes evident that one of the four directors of the association - Armstrong, Crandall, Thompson or Willard - is the secret leader of this gang and provides them with shipment and route information necessary for the gang's successes.
