As a child, Park Hoon (Lee Jong-suk) and his father were kidnapped by North Korea. In North Korea, Park Hoon was trained to become a doctor by his father who was already a famous doctor. Park Hoon became a genius thoracic surgeon. He deeply fell in love with Jae Hee (Jin Se-yeon) in his high school. Park Hoon's father then died and he tried to flee to South Korea with.
