The Sickle or the Cross (1949)

Reverend John Burnside, American missionary in the Far East, prepares to return home after twenty years to take up the fight against Communism. The Reds imprison him and send in his place a spy who is his double, but who is instructed to come out for Communism. The spy is accepted in Burnside's home town, and he reports to local Communist headquarters, where James John, prominent local businessman but in reality a Red agent, has instructions to assist him in all details of his mission. He does a series of personal appearances and radio interviews and talk shows, using an anti-Communist approach.