Convenience store clerks Chrissie (Chrissie Chau) and Katy (Katy Kung) decide to get back at their sleazy manager Leo (Leo Chim) by having their friends pose as robbers and hold up the store, but events escalate out of control into murder. What started as an elaborate prank sets off a butterfly effect of crime, consequence, and desperation as more and more people get pulled into the mess.