I just finished two scarily good books on North Korea. The first, Under the Loving Care of the Fatherly Leader, is a comprehensive history of Kim Il Sung and Kim Jong Il's reigns. The author traveled to NK several times as well as interviewed defectors. It's a terrifying picture of what life in North Korea is like, and more than that, it explains how it got that way. The second, Nothing to Envy: Ordinary Lives in North Korea, is an even scarier picture of what life is like in NK. It's a series of stories from defectors. Each comes from a different background: a soldier, a pediatrician, a teenager, a longtime party loyalist, etc. It really delves into the level of brainwashing the North Koreans have undergone as a society.

If you're interested in North Korea, these two books are excellent. Under the Loving Care of the Fatherly leader is one of the most detailed books on NK out there IMO. Definitely not pop history.