North Korea is a country landed in Asia but unlike the rest of the world, it is a state that is completely cut off from the world. It is also in an internal conflict with the other side of Korea, knows as South Korea. Lieutenant Commander Steve McGarret went here to help Agent Jenna Kaye to find her fiancee, only to discover that Kaye was actually working for crime boss, Wo Fat.
Steve was eventually captured and tortured for information in regards to "Shelburne" while Kaye who had discovered that her fiancee was actually dead was later shot dead by Wo Fat but not before she helped aid in Steve's escape.
Thankfully, Steve's colleagues, Detective Danny Williams, Lieutenant Chin Ho Kelly and Officer Kono Kalakaua with Steve's mentor, Joe White and a Navy SEAL team managed to get to North Korea to save Steve and bring him back to Hawaii although Wo Fat later escaped.