An Eastern Bloc espionage ring operating in the Los Angeles area is unraveling. One of its key operatives, Jan Anka, has manipulated a draftsman at a missile plant into providing copies of key blueprints. The plant employee's German girlfriend is being held in East Germany -- or so he believes. It turns out the girlfriend has really been dead for eight months. The draftsman attempts to quit the ring but Anka kills him. Now, the FBI has been drawn into the case, led by Erskine and Colby. Things become more complicated. Anka has posed for years as another man. A woman shows up -- the daughter of the man Anka has pretended to be. Now she's in danger as the espionage ring becomes more desperate.