Bok-Nam (Park Yoo-Sun) is an elementary school student who feels like she just doesn't fit in. She lives with her family that consists of her grandmother (Kim Ji-Young) with Alzheimer's disease, mother (Lee Mi-Young) who runs a chicken restaurant, unemployed father (Lee Sung-Min) and bully older sister (Nam Bo-Ra). Bok-Nam is not happy with her family. One day, she begins to think that she is Flashman, who came from outer space, and she wants to return to her place of origin.