But today North Korean defectors number in the tens of thousands, perhaps hundreds of thousands — the full scope of the exodus is not clear. They sneak across the river to China, where they live as fugitives, or flee through deserts or jungles to Mongolia, Burma or Thailand.
       Their accounts have gained credibility by their number and their consistency, and by corroboration from the few outsiders who have worked in North Korea. In dozens of interviews in Seoul over two years, defectors painted a picture of cruelty, hardship and repression that made escape seem their only option, no matter the cost.
       They often escape with the cruel knowledge that they have doomed their loved ones still inside. Leaving North Korea illegally is a high crime; going to South Korea is considered treason. Families — even distant relatives — of those who do so might be blacklisted, stripped of their jobs, imprisoned or killed. Many find freedom more complicated than they imagined, and their present haunted by the past.