The 49th Man

U.S.Security Investigation Division chief Paul Reagan (Richard Denning) assigns John Williams (John Ireland) to hunt down a subversive group that has been smuggling A-bomb parts into the United States in specially designed cases. Williams traces the ring to Marseilles, France, where he meets Margo Wayne (Suzanne Dalbert) at a waterfront café and discovers she is part of the plot. When recalled by Regan, Williams is informed that he has been engaged in a "war games" security check to test America (imdb)