Tool of the trade
Nicholas Foley appears to be an ordinary American psychology professor. He is, in fact, a Russian spy, inserted into the United States after World War II, joining the American army, attending American universities, falling in love and marrying an American, but always in touch with his Soviet superiors. All he ever does in the way of spying is turn in the names of people who might be "turned." But then he makes his momentous discovery. He isolates an ultrasonic frequency that causes anyone within earshot to do whatever he is told. A few demonstrations send both the Russians and the Americans after Foley with a vengeance. Eluding both, Foley uses his tool to strike a blow for world peace, as envisioned by a Sixties hippie, his wife