what movie is scary movie 4 based on

Scary Movie 4 is a 2006 American science fiction parody film that is the fourth installment in the Scary Movie film series). The movie is a parody of several horror and science fiction films, including War of the Worlds, Saw, The Village, and The Grudge). While the movie is a parody, it does have a plot that follows characters as they navigate through various comedic situations.