a spy who works against enemy espionage

Counterspy was an espionage drama radio series that aired on ABC and Mutual from May 18, 1942 to November 29, 1957. David Harding (Don MacLaughlin) was the chief of the United States Counterspies, a unit engaged during World War II in counterespionage against Japan's Black Dragon and Germany's Gestapo. With spies still lurking in the post-war years, the adventures continued apace well after World War II ended.