In a small rural town, a young boy named Jesse Aarons trains all summer to become the fastest runner in school. Despite his efforts, he is outpaced by Leslie Burke, a new girl who becomes his neighbor and classmate. Initially taken aback by her victory, Jesse soon befriends Leslie, drawn to her imaginative and vibrant personality. Together, they discover a rope swing in the forest, which serves as the gateway to a magical kingdom they name Terabithia. In this secret world, filled with fantastical creatures and challenges, Jesse and Leslie reign as king and queen. They find solace and strength in Terabithia, which offers them an escape from the difficulties of their school and family lives. Through their adventures, Jesse and Leslie teach each other the value of friendship, courage, and the power of imagination.

As their bond deepens, the magical realm of Terabithia begins to influence their lives in the real world, helping them to confront and overcome personal struggles. Jesse, an introverted artist, finds confidence and opens up to the possibilities of friendship and creativity. Leslie, with her fearless and imaginative spirit, helps Jesse see the beauty in the world around them. Together, they face bullies at school, navigate the complexities of family dynamics, and learn valuable life lessons. Their friendship transforms them in profound ways, leaving a lasting impact on their lives and shaping their journey towards adulthood.