One day they are cheated out of their ill-gotten gains in an encounter with Jia Wu Dao / Silver Fox (Lau Kar Wing).

After surpassing the fighting skills of "ordinary people", Yipao soon discovers that Jia Wu Dao is a murderer.

As their fight moves outside of the wine shop, the fat beggar and Yipao defeat Jia Wu Dao, killing him with spiked vines, finally avenging Taipao's death.

The fat beggar reveals that he is an undercover detective trying to arrest criminals, particularly Jia Wu Dao.

The domestic Hong Kong theatrical release of Knockabout' ran from 12–25 April 1979, taking HK $2,830,519.