Isaac Don Levine (January 19, 1892 – February 15, 1981) was a 20th-century Russian-born American journalist and anticommunist writer, who is known as a specialist on the Soviet Union. He worked with Soviet ex-spy Walter Krivitsky in a 1939 expose of Stalin's purges and other terrorism in the Soviet Union. Later he worked with Whittaker Chambers, a defector from the American Communist Party, to reveal agents in the United States government. Source: Wikipedia (en)