Something very real did happen 25 centuries ago in a narrow pass on Greece’s northern coast called Thermopylae–the name means “the hot gates.” In August of 480 B.C., a force of about 7,000 Greek soldiers assembled there, including 300 Spartans under the leadership of their king, Leonidas. The Spartans were sick, scary fighters, brutally trained from childhood, the ancient equivalent of special forces. They were there to meet an army of more than 250,000 Persians under the command of King Xerxes. The odds were ludicrously bad, the outcome a foregone conclusion. Most of the Greeks retreated, but the 300 Spartans, the hard core of the Greek army, chose to fight on, using the natural strategic advantage of the pass. They lasted three days–beyond all hope, beyond what should have been militarily possible–and then they died. Their refusal to surrender their freedom to the Persians inspired the rest of the Greeks, who ultimately rose up as a nation and beat back the invaders. That was then. On March 9, a movie about the Battle of Thermopylae, called 300, will hit theaters. It was made by a young director, stars nobody in particular, and it looks like nothing you’ve ever seen. Very little in 300 is real except the actors. Sets, locations, armies, blood–they’re all computer generated. It’s beautiful, and it might well be the future of filmmaking. But should it be? In 1962 a boy named Frank Miller went to the movies with his parents. The movie was Rudolph Maté’s The 300 Spartans. Miller was 5. “It had a deep, deep effect on me,” Miller says. “I actually snuck across the theater in order to confer with my dad and make sure the heroes really were dying. I stopped thinking of heroes as being the people who got medals at the end or the key to the city and started thinking of them more as the people who did the right thing and damn the consequences.” When Miller grew up, he created a comic book about the Battle of Thermopylae called simply 300. Miller’s account of the battle–now doubly refracted through two media–was read by a movie director named Zack Snyder. Snyder, 40, cut his teeth on high-concept, effects-heavy TV commercials. He made his feature debut in 2004 with a feather-light, razor-sharp remake of the zombie classic Dawn of the Dead. Snyder is something of a dork. Only a dork–the finest, most discriminating of dorks–would have read 300 in the first place. When Maté made The 300 Spartans, he packed up his cameras and his actors and his caterers and went to Greece. When Snyder made 300, he did what dorks do: he locked himself in a room with a bunch of fancy computers. Snyder is one of a small, hypertechnical fringe of directors who are exploring a new way to make movies by discarding props, sets, extras and real-life locations and replacing them with their computer-generated equivalents. Cinema has always had a tenuous connection to reality; they’re severing it almost completely. It’s a technique loosely known as “digital back lot.” George Lucas was a pioneer, as was Kerry Conran, the lonely genius responsible for the much praised, little-seen Sky Captain and the World of Tomorrow. In Robert Rodriguez’s cult hit Sin City , practically nothing is real but the people. It’s not so much cinema as synema. And it’s creeping into more mainstream movies: in Blood Diamond, a tear was digitally added to Jennifer Connelly’s flawless cheek, after the fact, to put the exclamation point on a crucial scene. For Snyder it was simply the only way to get the look of Miller’s 300 off the page and onto the big screen. “One of the early versions of the movie I wanted to do was a Lemony Snicket kind of method,” he says, “where you build a giant environment in a giant hangar, and it’s an actual 3-D world, but it’s just done with painted backgrounds. But it’s incredibly expensive, and you need the space. When I saw Sin City I said, ‘You know what? I could do that.'” He could and did. Snyder shot 300 almost entirely in a warehouse in Montreal. He filmed exactly one scene outside, and that was just because it’s hard to do galloping horses in a warehouse. Strange things happened in that warehouse. The digital–back lot approach places an immense burden on the director. “Zack would go, ‘Come and see this stage!'” says Lena Headey, who plays Leonidas’ wife. “And we’d go, and there’d be, like, a rock. And we’d be like, ‘Has he taken acid this morning? Or what’s he looking at?'” Snyder had to make his actors see what he saw, and he saw things that weren’t there yet. “Every now and then I’d stop and go, ‘This is crazy!'” he says. “‘What are we doing?’ And then we’d shake that off and get back to work.” Ironically, acting on the digital back lot is a lot like plain old nondigital stage acting. It’s just lights and bare floorboards. “You don’t have any boundaries,” Headey says. “You don’t have any emotional props. You can’t do this thing of, ‘Oooh, I’m going to sit on this chair because I feel sad now,’ or ‘I’m going to hit this!’ You don’t have any of that.” With so much computer-generated make-believe going on, the actors’ physicality is the movie’s only link to the real world. To turn Hollywood pretty boys into Spartans took eight weeks of intense dieting, exercise and martial-arts training. Onscreen their ripped abs look as if they’re trying to bulge their way out of their stomachs.