Summer blockbusters have never been known for their depth.
But a slate of big-budget movies is trying to change that as Hollywood turns to 50-year-old technology to keep theaters packed.
Columbia Pictures' animated film "Monster House" opens today in 3-D, the latest film to use a technology once dismissed as cinematic gimmickry to heighten the realism -- and add just a touch of the thrill ride -- to theatrical releases.
Filmmakers say the technology brings a new dimension to the big screen, accentuating the menacing maw of the possessed "Monster House" or lending dramatic realism as the Man of Steel rescues Lois Lane and her family from a sinking yacht in "Superman Returns."
The studios and exhibitors see 3-D as a lure to keep people coming to theaters instead of watching movies at home on their big-screen TVs.
"With rising production costs and especially marketing costs from the studios, we needed a way to help 'eventize' our most important productions," said Dan Fellman, president of domestic distribution at Warner Bros. Pictures.
For an industry that recycles its story lines -- "Poseidon" and "Miami Vice" are recent examples -- it's little surprise that the studios are dusting off old approaches for prying audiences out of their living rooms.
In the 1950s, studios fearing the encroachment of television grabbed for the polarized glasses and embraced 3-D technology. The inaugural 3-D movie, "Bwana Devil " -- a jungle adventure that promised "a lion in your lap" -- was such a rousing hit, other studios began creating their own 3-D films.
Although early 3-D enjoyed some commercial success -- Warner Bros.' horror thriller "House of Wax" starring Vincent Price was among the top 10 grossing films of 1953 -- projection and photographic errors, together with filmmakers' impulse to thrust spears into the audience's eyes, caused people to leave the theater with headaches or sick stomachs.
New digital projectors make today's 3-D movies more lifelike and less likely to induce queasiness.
Warner Bros. was the first big studio to experiment with new 3-D technology in a major release, and its 2004 "Polar Express" in Imax 3-D triggered a stereoscopic revival. Robert Zemeckis' animated version of a child's Christmas Eve trip to the North Pole reaped $128 million in 3,650 U.S. theaters in traditional film projection -- and $45 million more when shown on 83 Imax screens in 3-D.
It was so popular with audiences, Imax offered a repeat showing in the 2005 holiday season.
The experiment has propelled a flood of 3-D projects, including "The Ant Bully," which opens in Imax 3-D on July 28, and Sony Pictures Animation's forthcoming "Open Season."
"You have to keep pushing the audience experience," said Yair Landau, president of Sony Pictures Digital. Dramatic visual effects are no substitute for telling a story well. "If the story works you can make the experience more visceral in 3-D."
Indeed, "Monster House" -- a collaboration between Sony Pictures Imageworks digital production studio and Zemeckis' Imagemovers Production -- was conceived as a 3-D project.
"Once I saw the 'Polar Express' offered in 3-D, I saw it could actually take a story somewhere else," said "Monster House" director Gil Kenan.
"It shattered the idea of going to a movie as a passive experience. It becomes something more akin to a thrill ride, an amusement park ride. It makes the audience feel like they're strapped in and moving through the story."
Kenan and other contemporary filmmakers have learned a few lessons from the excesses of early 3-D experiments -- to use restraint, rather than "poking a candelabra into your eyes for an hour and a half." Otherwise, the audience suffers eye fatigue.
"Monster House" employs 3-D to amplify the film's spooky atmospherics. In one scene, the main character, a boy named DJ, scales the steep tower of a wrecking crane and the 3-D heightens the sense of vertigo.
Similarly, "Superman Returns" director Bryan Singer chose, largely for technical reasons, to limit Imax 3-D to those moments when the Man of Steel dons the cape. So when Clark Kent takes off his glasses, audience members put theirs on.
In one flashback to Clark Kent's days as a teenager on a farm in Smallville, he bounds higher and higher through the cornstalks, ultimately crashing through the roof of a barn and stopping inches above the hay-strewn floor. The top of his head is in the center of the screen.
"The cornstalks are right there in your head," Singer said. "It puts you right in the scene. Having been there, having made the movie on that actual farm that we built, not since then did I feel I was put there again."
The digital conversion of cinemas is propelling the 3-D renaissance.
The 3-D technology of the 1950s used two synchronized projectors to simultaneously show two films on screen -- one for the right eye and one for the left. The audience wore polarized 3-D glasses to filter out the image intended for the other eye. (Think of polarized lenses as slots: If the light from the film aligns with the slots, it enters; if not it's blocked.) The result was an image that appeared to float off the screen.
Today, the polarized glasses are the same. But digital technology has eliminated the need for two projectors.
Digital projectors can run at speeds of as many as 144 frames per second. Companies such as Real D, which have signed deals to bring stereoscopic film to theaters, place a shutter in front of the projector to swiftly flicker back and forth between the images intended for the right and left eye.
Another company, NuVision Technology of Beaverton, Ore., uses lightweight glasses that filter the image.
The results are considerably easier on the eyes.
Regal Entertainment Group operates 13 Imax and 38 Real D screens out of its 6,383 screens. It plans to add more Real D screens in anticipation of the "Monster House" opening.
"I think people seek out new technologies," said Kevin Keller, Regal's film vice president. "We've had very favorable response."
The jury's still out on whether audiences will embrace 3-D, or whether it will go down as another cinematic novelty.
"Time will tell if it really is the killer app for theatrical," said Andy Maltz, director of the Science and Technology Council for the Academy of Motion Picture Arts and Sciences.
"With digital distribution and projection systems, you can do things that you've never been able to do before.... What the studios choose to do with that to draw people out of their homes, what creativity goes into that, we'll see."