From a ruggedly sheepish archaeology professor who has a way with a whip to a debonair inventor with a knack for making exoskeletons that fly, science -- or at least the appearance of science -- is storming its way onto movie screens this summer.
But as fantastical as these films may seem, experts say these characters, whether they're green, ill-tempered scientists or amnesiac butt-kicking former CIA operatives, are grounded in more than the stuff of comic book lore.
The summer blockbuster "Iron Man" falls firmly into this category, according to James Kakalios, a University of Minnesota physics professor and author of "The Physics of Superheroes."
"When you're asking the audience to buy into something as intrinsically [fantastical] as superheroes, the more you can ground everything else in realism helps with the suspension of disbelief," he said.
Based on the classic comic book character, "Iron Man" follows Tony Stark, an inventor and venture capitalist who makes high-tech war weaponry. When Stark, while on a trip to Afghanistan, is captured by terrorists who want him to make weapons for them, he creates an exoskeleton that allows him to fly and escape.
"The good superhero stories require only one miracle exemption from the laws of nature. One miracle exemption [in 'Iron Man'] is that he builds this arc reactor, this small power supply that powers his suit. Once you buy into that," it's easy to go along with the rest of it, said Kakalios. "You see him trying to debug the suit, you see him develop the hand clusters as flight stabilizers. That's all within the realm of believability."
In the comic book and the movie, Stark controls the suit without voice commands or pressing buttons. Basically, according to Kakalios, Stark thinks the suit into motion. If he wants to fly right, the suit flies right. If he wants to slow down, the suit slows down. The technology in the movie is not so far from reality.
"Researchers are developing helmets that can detect your EEG patterns that are transmitted to electrical signals and sent wirelessly to computer screens," said Kakalios.
If you think about moving a cursor on a computer screen to the left, the helmet will pick up on that thought and move the cursor to the left.
"It's for the treatment of people who are paralyzed or who have prosthetic limbs. You could think about moving the limb and it moves," he said. "If you had asked me in the '60s which thing in the year 2008 would be the closest thing to being a reality, the last thing I would have picked would be the cybernetic helmet. But we still can't take flying cars to work. Sometimes I feel totally lied to."
"Iron Man" also gets science points for its smaller details, said Kakalios, who is currently consulting on a film version of the Watchmen, which he calls "the 'War and Peace' of comic books."
"You see him in the lab soldering, using the same equipment we use in the lab," he said. "It was a nice little touch, and it was clear that they are trying to show that this is a guy who really knows his way around the lab. Little touches like that work well. ... If they have something that's physically correct, it's almost like an inside joke."
Comic book characters, of course, have a long history with Hollywood and, by nature, with science: "The X-Men," "Batman," "Spiderman," "The Fantastic Four" -- the list goes on and on.
"Most people don't understand science and technology, and we look to it as where miracles come from," said writer Bob Weinberg, co-author of "Science of Superheroes." "This is modern mythology. ... This is our magic."
According to Weinberg, that's why we often see scientists and geeks portrayed as superheroes, like science-loving Peter Parker who gets bitten by a radioactive spider that turns him into "Spiderman," or Dr. Bruce Banner, a physicist who gets hit with atomic energy that allows him to turn into a green, mean fighting machine -- the Hulk.
It's a revenge of the nerds fantasy that comic book writers, and the Hollywood studios that bring their stories to life, thought audiences could relate to.
"It's very much the American dream," Weinberg said. "I think that's really why it works."
In movies, Weinberg sees both the scientific truths and the myths. In "Spiderman," Parker's "spidey sense" is something that spiders actually have; the hair on their bodies is sensitive to the motion of the air and can alert them when something's approaching them.
On the other hand, spiders aren't particularly good fighters, according to Weinberg, nor do they swing from structures on strands of silk.
Weinberg also takes issue with the upcoming movie based on the Incredible Hulk. The atomic energy that hits Banner -- gamma rays -- wouldn't make him a superhuman fighter.
"They definitely do not mutate people. They just kill people," Weinberg said.
But superheroes, of course, aren't the only on-screen characters that get to revel in the "geek chic" of scientific theory.
In the "Bourne Identity" series, Jason Bourne, played by Matt Damon, is an abandoned supersecret CIA agent with a serious case of amnesia. In the first film, directed by Doug Liman, sailors find him floating in the water with no memory of who he is; he still, however, retains a memory of how to speak in English and several other languages, tie intricate knots and, of course, fight with both guns and his body.
"I'm interested in honest characters more than I'm interested in honest science," Liman said by phone from a movie set in Africa. "I discovered immediately that the reality of amnesia wasn't going to be valuable to Jason Bourne and that the movie was going to have to exist in a slightly altered reality."
After scientists told Liman that Bourne couldn't get that kind of amnesia from just a bump on his head, he tweaked the story; instead, Bourne's brain was altered in the CIA secret program Treadstone.
"I could ground the rest of the movie in the science of the CIA. ... What's in the movies that's not in the book is the sense of some kind of high-tech brain-altering process that Jason Bourne was put through -- a kind of fantasy thing, so his amnesia could be connected to that, rather than a run-of-the-mill trauma," Liman said. "It just means that when I learn that what I want to do could never [happen] in real science, I'll just adjust the movie ... so that I'm remaining honest even if I'm distancing the truth."
According to Dr. Giulio Tononi, a neuroscientist at the University of Wisconsin-Madison, the amnesia exhibited by Bourne in the film, while not common, is certainly a realistic depiction of a condition known as dissociative amnesia.
Dissociative amnesia is generally caused by a "psychological conflict," Tononi said, in this case, Bourne's moral discomfort with his transformation into a brainwashed international assassin.
"Other aspects of his memory are perfectly intact, for instance, what is usually called working memory," Tononi said.
Bourne remembers phone numbers and license plates. He also remembers old skills, such as how to tie a knot, but he doesn't know why or how he learned them.
"That kind of memory is typically preserved. People very well remember the tasks of tying knots or playing the piano or playing a video game," Tononi said. "They forget about the episode [of learning], but they don't forget the skill."
But Tononi didn't buy everything in "Bourne," especially the main character's fighting ability.
"I've not seen anybody behave the way he does when in a fight," he said.
Liman also consulted scientists when making his sci-fi teleportation flick, "Jumper," earlier this year. In the film, the main character, David Rice, has a genetic mutation that allows him to teleport, or "jump," from place to far-flung place instantly, just by thinking about it.
With "Jumper," "it was the same kind of consultation. Go see a scientist, be told what I'm doing is total hogwash and then do it anyhow," he said. "I come from a passion for science and so I'm being a little bit glib when I write off the scientists, but I try to keep it as close to the science of 'could it really happen?' as opposed to saying it could never and just stopping."
In the movie when Hayden Christiansen jumps there is evidence of some kind of atmospheric disturbance — papers shuffle, furniture is knocked over, bystanders hear a dull roar — but it's more like a strong gust of wind than the atomic bomblike energy it would actually produce.
"In a person there is enormous amount of energy. If I just converted you all into random energy, it would be like a huge hydrogen bomb went off. In order to just remove a whole person, you have to get rid of all the megatons of energy to go somewhere," MIT physics professor Max Tegmark told me in an interview earlier this year. "I think Doug Liman is making it as realistic as he can, but I loved how he phrased 'slight implosion' [in the script] as Hayden Christiansen rushes out."
In the end, however, despite the scientific flaws in "Jumpers," the film, like other science fiction before it, will continue to inspire both aspiring lab rats and experienced scientists, according to Tegmark, who has been similarly inspired by writer Isaac Asimov.
"I think it's great when directors … try to put as much physics as they can" in movies, he said. "Sci-fi doesn't just get people into science. Sci-fi can ask scientists to ask really basic questions about the nature of reality and sometimes that can lead to really useful applications. Teleportation is a case in point."
Similarly, Kakalios uses sci-fi movies as a teaching tool in his classes at Minnesota.
"You talk to people and they're very insecure about their math and science knowledge. But if you start talking about Spiderman or Superman, they don't expect it to find physics," he said. "In this weak moment, you can actually teach them something."
You can see Dr. Giulio Tononi and director Doug Liman talk about the science of "The Bourne Identity" at the World Science Festival.