A former arm-wrestling champion raised in the U.S. returns to South Korea for a tournament that could return him to glory, but he finds his life complicated by the appearance of the biological family he never knew.

The friendship between a lawyer who will do anything to make money and a nursing home volunteer.

While his mother is sick in the hospital and his father is always busy, nine-year-old Da-yi eats, sleeps, and manages to do everything well by himself. One day, he heads out on a short but lengthy trip to meet his mother with the help of his friends.