The opening sequence is an homage to Saw, with two men waking up in a dingy basement, chained to the wall. If they want to escape, they must use a nearby hacksaw to cut off their own feet. The humor in the scene comes from the fact that the men are Shaquille O’Neal and Dr. Phil.

From there, we pick up with Cindy Campbell (Anna Faris), our heroine from all four movies. She takes a job as a personal care aide in a house that happens to be possessed by a ghostly Asian child, a la The Grudge. Living next door is Tom Ryan (Craig Bierko), a divorced dockworker whose attempt to reestablish the bond with his two children is interrupted by alien invasion. Any similarities to War of the Worlds is purely intentional. Cindy and Tom try to fight the aliens, which leads them through a series of scenes that will look familiar to anyone who has seen The Village, Brokeback Mountain or even Million Dollar Baby.

Leslie Nielsen also returns as the President who, upon learning of alien attack, refuses to act until he hears the ending of the children’s book he is helping to read in a classroom. (Michael Moore must be rolling in the aisles somewhere.) No one is safe from being a target. The movie ends with an over-the-top bit mercilessly mocking Tom Cruise’s infamous couch-jumping Oprah interview.

This is the level of humor you get in a Scary Movie. It’s frequently silly, sometimes stupid, occasionally hilarious, and often vulgar. Some critics have taken this series as a sign of the cinematic apocalypse, but I’m not so sure. You know exactly what you’re going to get, and you get it. Is that so wrong?

Earlier this year, I panned Date Movie, which spoofed “chick flicks” in the same style that Scary Movie spoofs horror films. I complained that Date Movie did nothing but reference other films, which quickly became old. So why did I hate that film but laugh at this one? There are two reasons. First, Date Movie used a connect-the-dots strategy where it just meandered pointlessly from reference to reference. Scary Movie 4, on the other hand, borrows actual chunks of plot from the titles it parodies, assembling them into…well, not really a story, but a take-off on a story. Put another way, it mocks the conventions of the genre rather than just individual scenes of other films.

Second, and more important, is that Scary Movie 4 was directed by David Zucker and written by Pat Proft and Jim Abrahams. These are the guys who created Airplane and the Naked Gun movies. They invented this genre and know how to do it better than anyone else. Although they do go for the obvious jokes at times, there is also a lot of invention in their humor. Because the film relies heavily on sight gags, it’s near impossible to describe them in print and have it be funny. That said, I did laugh when Tom Ryan chopped firewood, using Duraflame logs instead of real ones. Ditto for the scene in which Cindy talks to the ghostly Asian boy. Subtitles provide English translation, but if you listen carefully, you’ll hear the actors saying things in faux Japanese (“Mitsubishi Sony samurai!”). And then there’s the Mike Tyson cameo, which is wrong in so many wonderful ways…

The basic formula of this genre is to throw as many zany jokes as possible at the wall and hope enough of them stick. Some admittedly don’t; I mean, there must literally be 50 shots of people getting hit in the head/face with hard objects. Other things just don’t have the sizzle that we hope for, like a sequence in which everyone in the United Nations becomes naked after being zapped by an alien ray.

For me though, the ratio of hits to misses was high enough to recommend Scary Movie 4 for other fans of the series. It’s actually inventive in the way it ties together the primary films being spoofed (The Grudge, War of the Worlds, Saw) and I can’t deny the fact that I laughed on a fairly regular basis. Yes, the Scary Movie pictures are about as fluffy and inconsequential as they come, but I don’t see anything wrong with the occasional bit of mindless entertainment. Sometimes you just need a good, old-fashioned case of the giggles.

( out of four)

Scary Movie 4 is rated PG-13 for crude and sexual humor throughout, some comic violence and language. The running time is 1 hour and 24 minutes.