A Traitor’s Heart is the second in a trilogy of books featuring Revol Rossel, a former militia lieutenant in Stalinist Leningrad. His nemesis, Major Nitkin, who literally cut short his career as a prodigiously talented violinist in the Leningrad Conservatory by cutting off two of his fingers and mutilating others, but also has the top-level connections in the Kremlin to protect him. At the beginning of the A Traitor’s Heart , Rossel is so far...