A year ago, sci-fi fans were treated to the ultimate invasion flick: Independence Day. Now Earth has been besieged by an even deadlier force: Tim Burton's imagination.

Burton, the master producer-director who's brought to life everything from Batman to The Nightmare Before Christmas, is at it again. And if he's been cleverer, he's never been funnier.

That's because Mars Attacks is even more than a spoof of '50s sci-fi films, which it is, or a modern-day political satire, which it is. It's an all-out attack on all that's tacky and all that's holy in America today, with few distinctions drawn between the two.

Leading the assault is Jack Nicholson in a rare dual role: That is, he plays two people instead of the usual one guy with two personalities. As the president of the United States, he's frightfully restrained, talking peace with aliens even though they've made no bones about turning his army into a field of skeletons. As Las Vegas developer Art Land, he's even more preposterous, pushing ahead with plans for a new hotel at the height of the firefight, arguing with his investors that even invading Martians are going to need a place to stay.

Assisting the president in one way or another is a star list worthy of a disaster film: Glenn Close as the first lady who's not going to have these slimy creatures in her home, no matter how important it is for intergalactic harmony; and Annette Bening as the New Age guruess who knows the aliens have come to solve all the Earth's problems.

Pierce Brosnan plays the pipe-smoking egghead who's certain the aliens have come in peace, even after they have him in pieces; Martin Short is a George Stephanopolous clone whose sexual appetite makes it possible for the aliens to feast on the White House staff; Rod Steiger is the nuke-'em general; Paul Winfield is the talk-to-'em general who gets nuked; Jim Brown is the former heavyweight champ ("The 'quaka in Jamaica"); and Joe Don Baker is the trailer-bound militia type whose wife will spot the aliens with their son, but won't give up the TV.

Still, the best bits go to Michael J. Fox as a hair-obsessed hard-news reporter and Sarah Jessica Parker as the puppy-toting talk-show queen abducted by the aliens, who find better a use for her than the networks have.

Then you have the aliens themselves. They're a sort of cross between This Island Earth and Rugrats. They're fun to watch, and they give Burton plenty of room to display his penchant for gadgets and goo.

As for the plot, take your pick. There are a half dozen or more rolling along at any one point. If one bores you, hang in there. Another will be along any minute.

Mars Attacks is far from perfect. Some scenes drag on too long, and some parts, like Danny DeVito's, seem to have little purpose other than to bring in one more star.

But at its best, which it often is, Mars Attacks is that rarest of things: A visual feast that doesn't skimp on the food for thought; an intelligent film about human imbecility; a techno treat that won't insult your intelligence.

Just everybody else's.