The daughter of a restaurant owner gets kidnapped. The water boy (who's almost a girl because his wee-wee was chopped off) want to free her. But therefor he first has to become a real man with real kung fu skills. So he starts training with an old guy

In Korea during the Joseon Dynasty, a young man is forced to marry the king's daughter despite being betrothed to another woman, triggering a series of tragic events.