One of the toughest places for intelligence officers to penetrate is North Korea. The hermetic, communist country allows few Westerners across its borders. Those who enter legally are kept on a short leash, with minders watching every move. Others aren't so lucky, like American journalists Laura Ling and Euna Lee, sentenced to 12 years hard labor for allegedly crossing into North Korea illegally.
One journalist, Tomas van Houtryve has been in and out of North Korea twice. He's captured rare images of everyday life there, and tells host Guy Raz how he got into the secretive nation.