Operation Solo is America's greatest spy story. For 17 years, Morris Childs, code named "Agent 58," provided the United States with the Kremlin's innermost secrets. Repeatedly risking his life, "Agent 58" made 51 clandestine missions into the Soviet Union, China, Eastern Europe, and Cuba. Because Morris was in effect the second-ranking man in the U.S. Communist Party, he was treated like royalty by communist leaders worldwide. They never knew he was...