When Kim Jong Un became the leader of North Korea in 2011, predictions about his imminent fall were rife. Instead, the opposite happened. He has solidified his grip on his country and brought it to the brink of war. Still, we know so little about him—or how he rules. Enter former CIA analyst Jung Pak, a go-to authority on the calculating young leader. From the beginning of Kim’s reign, Pak has been at the forefront of shaping U.S. policy on North Korea. Now, in this masterly book, she explains Kim’s ascent, from his power-consolidating purges to his abrupt pivot toward diplomatic engagement and his historic summits with President Trump. In piecing together Kim’s wholly unique life, Pak argues that his personality, perceptions, and preferences are underestimated by policy wonks, who assume he sees the world as they do. As the North Korean nuclear threat grows, this book is an insightful, authoritative biography of the enigmatic man who could rule the hermit kingdom for decades.