An alien with enhanced physical abilities falls victim to fate and romance, jeopardizing his 400-year wait to return home.
Do Min-joon is an alien who landed on Earth in 1609 during the Joseon Dynasty. He saves a girl named Seo Yi-hwa from falling off a cliff and misses his return trip to his home planet, leaving him stranded on Earth for the next four centuries.
He has a near-perfect human appearance, and enhanced physical abilities involving his vision, hearing and speed as well as a cynical, jaded view of human beings. Since Min-joon never ages and is forced to take on a new identity every ten years; he has worked as a doctor, an astronomer, a lawyer, and a banker, and is now working as a college professor. Though he is cynical about humans, he gradually changes his views on them when he gets involved with a childish actress.