Chen Chun and San are two low-level mainland gangsters who open their own gambling outfit. When Chen Chun winds up killing the owner of a rival parlor, he flees to Hong Kong where he soon falls in with a heroin-addicted hooker named Fang. They inevitably fall in love but soon their bliss is shattered with the news that Chen's gambling venture has been taken over by a notorious gangster called Bolo Guy, and his mainland girlfriend Meila has been killed. Chen goes back over the border looking to set things right.