"The Runaway King" is a children's novel by Jennifer A. Nielsen and is the sequel to "The False Prince." The story follows Sage, a young nobleman who has become the king of Avenia after a series of political intrigues. Despite his new title, Sage feels unprepared for the responsibilities of leadership and decides to run away to protect his kingdom from threats. As Sage embarks on his journey, he faces challenges that test his courage and resourcefulness. Along the way, he encounters old friends and new enemies, ultimately learning valuable lessons about friendship, loyalty, and the true meaning of being a leader.