It looks like you picked the wrong week to stop sniffing glue. You've been swimming in raw sewage, and you love it. If you think aliens are strange, you should see the way they pee.

If a sly grin of remembrance is growing in the corner of your mouth, you speak the language of the cinematic subsection known as the spoof movie. With all due respect to the Marx Brothers, Mel Brooks and others, the modern blueprint was laid out by 1980's "Airplane!" and has hit or missed all the way to the recent "Date Movie."

Now with "Scary Movie 4" scaring up record-breaking grosses at the box office, it's time to deconstruct this funny formula in an attempt to fully appreciate what audiences should make of it. Well, besides a hat or a brooch or a pterodactyl.

Rule 1: The More Jokes, the Better — Remember how the 'toons in "Who Framed Roger Rabbit?" could be killed by excessive laughter? Well, Bugs and Daffy may want to lobby for a surgeon-general-type warning on the posters of these films, the best of which fire gut-busting guffaws like machine guns. Quantity clearly rules over quality, but the movies that can elevate their B-grade material to something funny are the cream of the crop. The original "Scary Movie" has some jokes that burn themselves into your memory (like Shawn Wayans' impaling via a male member), and others that drop with a thud (references to "Kazaam" and the "Wazzup" commercial fad). During the second half of the flick when the filmmakers worry more about staying true to plot twists rather than keeping the random-joke stream steady, the movie becomes as pointless as Jimmy Fallon dancing in a Pepsi commercial.

Rule 2: Casting Counts — As a general rule, steely faced drama veterans (Lloyd Bridges, Charlie Sheen, genre superstar Leslie Nielsen) fare better than comedic actors (Jay Mohr and Christina Applegate in "Mafia"), up-and-comers (Chris Evans in "Not Another Teen Movie") or struggling stars in on the joke (Jenny McCarthy and Yasmine Bleeth in "BASEketball"). Dramatic actors excel at delivering preposterous lines with straight faces, an absolute must for the medium. Just imagine a future spoof movie with Morgan Freeman barking out something like this classic line from "Hot Shots!": "Alpha Velveeta Knuckle Underwear, you are cleared for takeoff. When you hit that nuclear weapons plant, drop a bomb for me!" Thinking about the same quote, uttered between the lips of Ben Stiller's knowing grin, isn't nearly as funny.

Rule 3: Don't Lose Sight of Your Gags — Mocking specific movie scenes is fine, but a truly great spoof movie is memorable because of the timeless sight gags. Three decades ago, audiences howled in laughter when they first encountered "Airplane!" pilot Ted Striker's drinking problem. The glass-to-the-forehead bit still works today. The same can be said for the "I know a little German" line in "Top Secret!" (a tiny person in lederhosen is revealed) or the moment in "Hot Shots! Part Deux" when two leaping paratroopers shout "Geronimo!" followed by a third in American Indian clothing who screams "Me!" A good spoof movie lulls the audience into expecting a tired movie cliché, then throws in the uppercut of an unexpected punch line. Even in 2006, the biggest laugh in "Scary Movie 4" isn't the "War of the Worlds" or "Saw" jokes, but a simple sight gag playing off the tired cliché of heroic characters jumping passers-by and stealing their uniforms.

Laugh. Scream. Repeat
Scare yourself silly by watching our 'Scary Movie 4' behind-the-scenes tour and cast interviews


Rule 4: Keep Your Mind in the Gutter (To a Point) — "Nice beaver!" Lieutenant Frank Drebin exclaims, looking up as his dress-wearing paramour climbs a ladder in "The Naked Gun: From the Files of Police Squad!" "Thank you," she replies, handing down a taxidermy display item. "I just had it stuffed." Hilarious. An out-of-control cat in "Date Movie" humping a corpse? All you hear are crickets. The best dirty jokes in spoof movies occur when it's the audience's minds that are making things perverted, allowing the filmmakers to rise above the obvious by pointing out an innocent malapropism. Otherwise it's as unpleasant as taking balls to the face.

Rule 5: Choose Your Cameos Wisely — William Shatner's incensed tirade over the "thousands of blinking, beeping and flashing lights" behind him was arguably the best part of "Airplane II," and Bruce Willis' cameo as an action hero was one of the biggest laughs in "National Lampoon's Loaded Weapon 1." But some stunt-casting cameos, like Mr. T in "Teen Movie" and Lil Jon in "Date Movie," make you wonder if the original script just read "insert freakishly eccentric celebrity here." If the star doesn't fit, you must acquit.

Rule 6: Bad Movies Cause Memory Loss — Timeliness is imperative to a successful spoof movie. But "The Village"? Seriously? "Scary Movie 4" spends much of its running time spoofing a flick from two years ago that nobody even liked. While a sendup of "Saw" taps into a cultural phenomenon by simply re-creating hallmarks of the franchise, "Village" jokes need to stand on their own since most audience members have blocked out whatever familiarity they have with it. On the flip side, Michael Jackson jokes in "Date Movie" and the "Scary Movie" flicks never grow old, and the "SM4" scene with Tom Cruise on "Oprah" is timely enough to keep that flick from jumping the couch.

Rule 7: You're Innocent Until Proven Spoofy — Anna Faris is cute, naive and looks like your friendly neighborhood baby sitter. So when the first "Scary Movie" had her reminiscing about "that time I puked green slime and masturbated with a crucifix — it was my first keg party," she can get away with it. Clueless Cindy Campbell is the latest in a long line of innocent heroines, dating back to bubbly Julie Hagerty ("Airplane!"), who put a smile on more faces than just Otto's when she manually inflated the automatic pilot. Every spoof movie needs a naive female lead that catches us off guard and throws us into a tailspin when her jokes turn dirty. As eager-to-please "Naked Gun" actress Priscilla Presley once asked while sexily slaving away at a pot roast: "How hot and wet do you like it?" Very hot, awfully wet, and unapologetically innocent, thank you.

Rule 8: There Are No Rules — A truly great spoof movie achieves a level of limitless anarchy that would have made the Sex Pistols proud. The filmmakers are free to ignore the rules of common sense, plot structure and even gravity. They would most certainly read, process and quickly disregard all the rules you just finished reading. To paraphrase Frank Drebin: All a truly great spoof movie needs to do is act like a midget standing at a urinal — and stay on its toes.

Check out everything we've got on "Scary Movie 4."

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