When Kim Jong Un became the leader of North Korea in 2011, predictions about his imminent fall were rife. Instead, he has solidified his grip on his country and brought the world to the brink of war. Still, we know so little about him—or how he rules. Offering deeply informed insights, former CIA analyst Jung Pak delves into Kim's character and motivations, while assessing his brutal purges, his abrupt pivot toward diplomatic engagement, and his historic—yet poorly understood—summits with Donald Trump.