Director Brian DePalma's career has been sustained by making audiences remember the one or two ingenious scenes he slips into his otherwise mediocre movies.

What do you remember about "Mission: Impossible?" The silent, ceiling-suspended computer room break-in and the bullet train finale, right?

Can you recall much of "The Untouchables," other than the "Battleship Potemkin"-styled shoot-out on the Grand Central Station staircase? Me either.

The opening tracking shot in "Snake Eyes" that follows Nicholas Cage around a crowded boxing arena? Brilliant. The rest of the movie? Pee-yew!

"Mission To Mars" is an attempt to make an entire film from such signature scenes, but DePalma is trying so hard that all but one of the picture's big set pieces are either overwhelmed by expensive special effects or riddled with unintentional laughs.

Set in the year 2020, the story revolves around the mysterious disappearance of the first humans to land on Mars and the rescue crew sent to find them.

Stuffing epic-sized scope into a movie that's lethargic at 113 minutes, "Mission" hurriedly establishes the heroes' family lives in a backyard pre-launch barbecue scene before jumping to 13 months later and 50 million miles away.

The first landing crew discovers a distinctly metallic outcropping under a Martian mountain. When they take a rover to investigate, an apparently sentient dust storm kicks up and swallows alive all but mission commander Don Cheadle ("Out of Sight") in that effects shot being used to sell the movie on TV.

When the dust settles, the steely center of the mountain is exposed, and guess what? Remember that grainy satellite photo of the surface of Mars, trumpeted by the Weekly World News to contain the giant image of a face...?

Meanwhile, the crew of the World Space Station in orbit around Earth panics when the Mars team's transmission stop suddenly and they organize a rescue mission with Tim Robbins and Gary Sinise at the helm.

So far, so good. In fact, this movie's Memorable DePalma Moment takes place during the second crew's approach to Mars, when the ship is bombarded by micro-meteorites that breach the hull. All the tension and excitement "Mission" has to offer comes in the desperate search for leaks, the spacewalk patch-up job and subsequent explosion that leaves the crew (rounded out by Connie Nielsen from "The Devil's Advocate" and Jerry O'Connell from "Body Shots") jet-packing toward a robot resupply vessel in orbit nearby.

Even before this episode is resolved, however, the picture starts slipping toward B-movie oblivion with corny suspension of disbelief moments hinged on low-rent sci-fi scripting. Anyone old enough to remember "Space 1999" might even start having flashbacks.

Although the film looks spectacular throughout (the Martian landscapes are very convincing, even if the surface appears to be made up of rust-colored charcoal briquettes), the contemplative pace is too slow for short attention span testosterone junkies hoping for another "Armageddon" and the scientific/philosophic bent too simplistic to become the "2001" companion piece DePalma is all-too-obviously striving for much of the time.

After some of the spacewalkers reach the surface in the supply capsule, they descramble a mysterious white noise signal full of hidden scientific formula (a la "Contact") and -- abracadabra! -- a door opens on the side of the Big Metal Head. Sinise, Nielsen and Cheadle then step inside for the soft-peddled, "2001"-on-Prozac episode, in which the origins of life on Earth are explained with state-of-the-art holograms, courtesy of the ancient Martian equivalent of Industrial Light and Magic.

The potential for a good movie is visible in "Mission To Mars," but it's just screaming "sell out!" from every frame. Dumbed down for mass consumption by a team of screenwriters collectively responsible for "Predator," "Hard Rain" and "Wild Wild West," the film is a montage of showy effects, blatant product placement (Isuzu, Kawasaki, Pennzoil, Dr. Pepper) and ideas lifted wholesale from much better films. There's a fine line between homage and rip-off. I don't know where exactly that line stands, but "Mission To Mars" crosses it with impudence.

And it's not just me. At the screening I attended -- sponsored by a radio station with an easily entertained listener base -- the audience giggled incessantly through the movie's "magical" moments and booed resoundingly when the credits rolled.