"The Beyonders" is a fantasy book series written by Brandon Mull. It follows the adventures of a young boy named Jason Walker and a girl named Rachel as they discover a magical world called The Beyond. In this realm, they encounter various creatures and face challenges that test their courage and friendship. The series explores themes of bravery, sacrifice, and the battle between good and evil. As Jason and Rachel navigate through The Beyond, they learn about their own strengths and the importance of teamwork. The story captivates readers with its imaginative settings and engaging characters.