Ah Kuo, Xiao Yu and Chubby are three country bumpkins living in the mountains with their cantankerous grandfather, who teaches the boys about discipline, dedication and devotion through martial arts training. Over the years, the boys have done a lot of kung fu training and have gained much in the ways of martial arts, including good health and a bond that keeps them inseparable. However, during an argument involving who is suppose to feed Grandpa's pet bird, it escapes and now they fear punishment. Not wanting to get into anymore trouble, they flee from home in an attempt to find the bird and bring it back so Grandpa won't know and this prompts the boys to take a trip to the big city, where their country way of life causes them to get into trouble and clash with the locals a little bit because they have no knowledge of city life. During the trip, the boys discover their Grandma and little sister Cheng-Cheng living the good life and so she takes them in to look after them, but their happy times together won't last: a notorious crime syndicate that the Young Dragons bumped into earlier has some unfinished business with them and now, they must utilize everything their grandfather taught them as they fight to protect themselves and their family from the very thugs who seek to destroy their unity.