Chor Won (Cho Seung Woo), who loves zebras and chocolate, is a cute and lovable kid who looks no different from his peers from the outside. One day, Chu Won is diagnosed with autism and his mom Kyung Sook faints when she hears the news. Later, Kyung-sook realizes that Chu Won has an extraordinary talent for running, and hopes that at least her son will not lose out to others in running, so she begins to train him.
Chu Yuan grew into a 20 year old lad, but his intelligence remained at the level of a 5 year old child, respecting his brother as a teacher, and as soon as he came out to the music, he began to dance around regardless of the venue and place, and as long as Chu Yuan was there the place would become a mess. Look at his behavior and tone of voice is no different from a 5-year-old child, but the strength of running that has been maintained since childhood is still number one.
One day, Jung Wook (Lee Ki Young), a famous marathon coach who has gotten first place in world competitions, comes to Chu Won's school when he gets penalized for drunk driving. Kyung Sook asks Jung Wook to teach her son how to run. At first, Jung Wook is annoyed with Chul Won, but as he gets in touch with him, Jung Wook is more and more touched by the simple and truthful Chul Won, and Chul Won opens up his heart to Jung Wook gradually. Jung Wook realizes that Chu Won has the talent of a marathon runner and decides to train him.