Why some North Korean defectors return to one of the world's most repressive regimes

He risked his life fleeing from one of the world's most repressive regimes, traversing a militarized stretch protected by barbed wire fences. Then a year later, he went back -- the way he came. More than one month since the man crossed the demilitarized zone from South to North Korea, much of his life in both countries remains a mystery -- as do his reasons for returning to the isolated nation