A profile of the late Richard Feynman – an atomic bomb pioneer, Nobel prize-winning physicist, acclaimed teacher and all-around eccentric, who helped solve the mystery of the Space Shuttle Challenger explosion.

NOVA delves into the history of secret communications and the people who wrack their brains to decipher them. The program probes the most celebrated of all cryptographic coups: the breaking of the World War II codes used by Japan and Germany and how code breaking helped shorten the war.