One year after training a young Freddy Wong (Jackie Chan) in Drunken Master, Beggar So / Sam Seed returns to find that his wife has adopted a son named Foggy.

Devastated, the boy runs away and takes a job at an inn, where he meets Rubber Legs and his student.

He overhears that they are looking for Beggar So and want to kill him, making Rubber Legs' Northern 'Drunk Mantis' Boxing supreme.

Beggar So sends Foggy to a sickness teacher for herbs to cure him, and the doctor teaches him a dreaded style called 'Sickness Boxing'.

The film closes with a freeze frame as Foggy leaps after his adopted father as the doctor watches on.