Two bumbling lazy co-owners named Cheese and Ham (Dicky Cheung and Eric Tsang) run a revenge-for-hire business. They have their share of scrapes and follies, but things seem to be going well until they are hired by a terminally ill man who wants his girlfriend (Joey Wong) killed. They reluctantly take the job and then back out once they both fall in love with the girl. Joey is a sweet and kind girl who usually helps others for reduce the sins for her father.

In 20 years ago, Lung was going to kill the father of Joey but failure. This leaded Lung to be in jail. Lung is planning to take revenge when he is released?