Book club edition. Inscribed and signed by author on title page ('to Robert 2005') 1/2 inch closed jacket tear, front jacket flap corner clipped. 1968 Hard Cover. xiii, [3], 580 pp. 8vo. Moscow, Christmas Eve, 1949. The Soviet secret police intercept a call made to the American embassy by a Russian diplomat who promises to deliver secrets about the nascent Soviet Atomic Bomb program. On that same day, a brilliant mathematician is locked away inside a Moscow prison that houses the country's brightest minds. He and his fellow prisoners are charged with using their abilities to sleuth out the caller's identity, and they must choose whether to aid Joseph Stalin's repressive state -- or refuse and accept transfer to the Siberian Gulag camps and almost certain death.