Cops in party store and people are beheaded

One night per year, the government sanctions a 12-hour period in which citizens can commit any crime they wish -- including murder -- without fear of punishment or imprisonment. Leo, a sergeant who lost his son, plans a vigilante mission of revenge during the mayhem. However, instead of a death-dealing avenger, he becomes the unexpected protector of four innocent strangers who desperately need his help if they are to survive the night.

Two years after choosing not to kill the man who killed his son, former police sergeant Leo Barnes has become head of security for Senator Charlene Roan, the front runner in the next Presidential election due to her vow to eliminate the Purge. On the night of what should be the final Purge, a betrayal from within the government forces Barnes and Roan out onto the street where they must fight to survive the night.

A group of office workers decide to have a party in the office building. Among other things, they want to have some drugs there. Their conversation on the subject is overheard by Joe Vickers, which is rather unfortunate for them, since Joe Vickers is a policeman. Even more unfortunate is the fact that Vickers is also an undead psychotic satanist, and instead of arresting them, he will make sure that nobody leaves the party alive...