Do Min-joon (Kim Soo-hyun) is an outsider that arrived on Earth in the year 1609, amid the Joseon Dynasty. As he tries to help a young lady, Yi-hwa, from tumbling off a bluff, he misses his excursion back to his planet and is stranded on Earth for the following four centuries.
He has a close impeccable appearance, improved physical capacities including his vision, hearing, and speed, and a skeptical, tainted view with respect to individuals. As time passes by, Min-joon is compelled to go up against another personality at regular intervals, as his human appearance never ages.
He has a close impeccable appearance, improved physical capacities including his vision, hearing, and speed, and a skeptical, tainted view with respect to individuals. As time passes by, Min-joon is compelled to go up against another personality at regular intervals, as his human appearance never ages.
In the present, he acts as a school educator. With just three months left before his hotly anticipated takeoff back to space, he meets Cheon Song-yi (Jun Ji-hyun), a renowned Hallyu performing artist who abruptly turns into his nearby neighbor. Gradually, he gets himself ensnared in Song-yi's insane and flighty circumstances, and discovers that she resembles the young lady he experienced passionate feelings for in the Joseon period. Min-joon tries to keep himself far from Song-yi as he needs to leave the planet, however frequently ends up neglecting to do as such.