Scientists and mathematicians have been pondering the notion of multiple universes for centuries. Theories have been suggested, books have been written, even psychics and astrologers have speculated that more than one of each of us exits, and although no hard facts uphold such a belief, many knowledgeable people feel certain of this hypothesis. Would you be given another set of life circumstances? Would you have the same job? Would you select the same mate? Would you be happier or more successful in another world? Or, given the opportunity, would you discover that your alter ego is someone nothing like yourself? What if he or she were evil incarnate?

When partners James Wong and Glen Morgan first contemplated their script, Morgan had been doing some reading on alternate universes and was immediately drawn to writing about the subject. "I had been reading Elegant Universe and some other books, and an article in Scientific American that explored the theories of parallel universes," Morgan says. "The idea that there might be an infinite number of universes with subtle changes gave us an interesting premise. The theory is that when a black hole is created, parallel universes are created at the same time only millimeters away from us. It's a more harrowing idea than the existence of extra-terrestrials because many of us already accept that possibility. "

"We posit that those universes are very similar to our own," notes Wong. "But comparable to the Rube Goldberg effect, the effect of one event can change history and the course of where each parallel life is headed.

"Matter is never fully destroyed," he says. "So we thought it would be interesting if there were parallel me's or you's in different universes. Each of ourselves is linked by an energy wave so that when one of us dies in one universe, the energy still exits in other universes. It just gets redistributed amongst all the surviving beings.

"In some of the more advanced universes we created, they've discovered how to travel between parallel universes through quantum tunnels or wormholes," notes Wong. "The same people who have ideas about parallel universes also theorize that wormholes exist. As they warp in space, they allow us to travel through these different dimensions. "

"A microscopic wormhole can appear anywhere," Morgan further explains. "But the ability to open it even four feet would take more energy than what exits in the universe. Since we can't really open such a wormhole, we came up with the idea of dissembling our characters so that they are able to get through those holes. Their atoms break apart and are sucked through this vortex and into the wormhole and are reassembled in the next universe. It's sort of like the transporter in 'Star Trek,' but the visual effect is much different. The Multiverse Authority is able to forecast where a wormhole will appear so that they can use what they call a quantum tunneler to transport their agents via this microscopic highway. "

"Those discoveries are what distinguish each universe from another even though the same sort of people inhabit each universe," says Wong. "We see five of those universes in this movie. "

The partners developed and honed their story while on a road trip to Las Vegas. When they returned to Los Angeles, they pitched their idea to Joe Roth who immediately gave them the go-ahead. "Joe had started Revolution Studios and they were interested in doing a sci-fi action film," says Wong. "Since Glen and I were interested in doing that too, we discussed the parallel universe idea as well as having one actor play several different parts.

"We needed to decide who would be the best opponent for the protagonist," he says. "If you use someone who is a really great fighter, that opponent would be himself. In terms of the action you have the hero fighting the anti-hero - dual roles played by the best martial artist in the world just magnified the potential of the action sequences. "

Todd Garner, the studio's production chief, promised the duo he could deliver Jet Li as the star. "Jet was making 'Kiss of the Dragon (2001)' in Paris," says Morgan. "Todd left on a Thursday and on Monday he called to say Jet was available, which was great because Jim and I never thought we'd ever work with an international star of such magnitude and incredible talent. "

Jet Li, who many regard as the world's greatest martial artist, was enthralled with the concept of the story and being able to play such diverse characters in one film. "I believe that more than one universe might exist," says Li. "I liked the plausibility of the idea. It was also a challenge to play three different people in the film; the same man yet different in each universe. Each man has a different energy. "

Li brought in writer Robert Kamen to add elements to the script that are essential to him in every film. "Jet likes to make every movie special as it relates to his life," says producer and Li's manager Steve Chasman. "If it's just an action movie and there's nothing an audience can take away from it, then he's not interested. This movie is about the quest for power and the many situations we're all faced with in our lives. At the same time, it's about the balance between good and evil.

"The good Gabe and the evil Yulaw are not really enemies," he continues. "Gabe simply doesn't want any part of what's happening to him and Yulaw believes he's somehow making order of all the different universes. "

"In this case Gabe is a balanced human with a wife, a job, and even a dog he loves," says Li. "He cannot understand what is happening to him as the energy force from his counterparts in other universes invade his body. He does not want to be Superman. The evil Yulaw cannot seem to stop himself as he continues on his rampage; as he kills he becomes overtaken by a high similar to a drug addict. His power grows and the addiction grows. But you must like both characters to play them well, even the bad guy. "

Yulaw doesn't really believe killing these other forms of himself is murder," explains Wong. "In his arrogant way, he believes that he is the best container of their life energy. He's just collecting what is rightly his, which is his own life force. "

Morgan poses the same question put to him throughout filming, "Are Gabe and Yulaw the same person? If we did our job well, the audience will not only see a movie with terrific action, but they'll walk out asking 'What is the other me like in another universe?' That's the same question put before Gabe but he doesn't have time to contemplate the answer.

"There cannot be night without day or good without bad," he continues. "We must accept the darker side of ourselves, it's just there. But Yulaw won't accept this fact so he wants to become God and have it all. Jet brought that overall life view to the project. "

A practicing Buddhist, Li is always willing to share his time and philosophy with the crew. He brings an air of tranquility to the set and also a passion to share some of what he's learned on his life journey with his audience. "I really want to talk to the audience through each of my films," the actor says. "Life is about balance. It is the Earth view. It's about trying to understand people, to walk in another man's shoes. It's also about focusing on today and not worrying about the future. "

Journalists and the public alike frequently ask Li if he will remake some of his most successful Chinese films for English speaking audiences. Although he is flattered by the request and is attentive to his audiences, he wants to challenge himself and move forward in his international movie career. "The audience has the power," asserts Li. "I try to listen to them and to a certain extent they dictate my path because their advice is invaluable, but I am more interested in doing things I haven't done before, as in this film. "

With Li set to take on three different roles, it was important for the filmmakers to surround their star with equally dynamic supporting actors who were also faced with the challenge of playing more than one part.

"Once Jet was involved we wanted to cast against type in terms of Jet's quiet demeanor," says Wong. "He is spiritual and composed, so we wanted to create characters who were the opposite; we needed the other agents to be aggressive and outwardly intimidating. "

One such agent is Yulaw's former partner, Harry Roedecker. A seasoned veteran of the Multiverse Authority, Delroy Lindo is now the man ordered to find and stop his old friend. "Roedecker's function is to prevent Yulaw from committing the ultimate act, from becoming 'the one' and throwing the universe into disruption and possible annihilation," says Lindo.

"It's fair to say this is a story about good versus evil," he continues. "I interpret the story as a parable about fascism, because it has to do with one man attempting to become this omnipotent, all-ruling, all-powerful being. My job is to stop him from becoming a supreme being. "

Lindo and Li worked briefly together on the action adventure "Romeo Must Die (2000). " "I've gotten to know Jet a little better on this film," says Lindo. "I was working on another film at the same time we did 'Romeo Must Die (2000)," so I just came in for a couple of weeks. This time we've spent more time working together. It was fun. "

"It was very comfortable for Jet to come to the set having worked with Delroy before," says Chasman. "Delroy is one of the finest actors I've ever seen, and he really compliments Jet. You're only as good as the people you're working with and they developed a great chemistry. "

Roedecker is joined in the hunt by another agent, Ethan Funsch, played by Jason Statham. "My character is brought in for this special assignment because Yulaw is a bit more than the usual kind of bad guy," says Statham. "Roedecker is more of a cop and I'm more of a soldier from a universe that's inhabited by criminals the likes of Hitler or Hussein, so Funsch is used to this kind of confrontation. He's used to getting his hands dirty with this type of criminal. "

Along with managing Jet Li, Chasman also represents Statham. "Jason is like a young, British Bruce Willis. He's incredibly personable and very engaging on screen. "

"I wanted Jason to change his accent," laughs Wong. "So that was a challenge for him and he did a great job. Jason's energetic and fearless. "

"Watching these three actors working together was amazing," says Morgan. "Coming from another culture, we would sometimes have to explain to Jet why something was funny and he would determine if it made sense for him. With Delroy, he always wants to know why his character is motivated to do something, say something, even stand somewhere; he keeps you on your toes. And Jason is just so eager to try anything. So you have an international star in Jet Li, a consummate, seasoned professional like Delroy Lindo and a newcomer like Jason with innate ability and a strong work ethic, it was interesting to watch how that dynamic worked. "

Rounding out the cast is Carla Gugino who portrays Gabe's devoted wife, Traci Katherine, as well as Yulaw's girlfriend, Massie Walsh.

"Carla came in last minute," explains Morgan. "And we were lucky she did. It's not a big role, but it's extremely important; if you don't like her, if you don't believe in her, then the whole story falls apart. "

"Carla is one of those performers who will try anything and run with it," says Wong. "When she was came on set as the different characters, even the crew didn't recognize her. She's the sexiest woman you'll ever see, and then she becomes this wonderful, grounded wife and professional woman. You see the different spin she puts on each character; it's a tribute to her talent. "

"T. K. is a very pragmatic woman and she loves Gabe very much," says Gugino. "From the moment we're introduced to her, she's in crisis because her husband who is a policeman is going through a very difficult time. We sense their love and the connection between them. She's a very real woman in every sense. Massie, on the other hand, is the quintessential femme fatal, a vixen who says very little but is effective in her own way. She's a human version of Jessica Rabbit.

"One of the first things Jet expressed to me was how important the relationship between these two characters was," she says. "For Jet the connection between Gabe and T. K. was the heart of the story. There is humanity here. I also liked the notion that one's soul is something more than our physical presence and that it might continue through more than just one life. "

While the filmmakers were hard at work casting, production designer David Snyder was creating the unique look for each of the five universes. The script is broken down into present time; near future; far future in which technology has advanced to a sophisticated level; a euphoric place called Happy Land where everything is clean and beautiful; and finally a dark netherworld that resembles Hell. "Because the plot of the film involves traveling through time and space, each one of these universes had to have a specific tone and look to it which included different textures and color palettes. We tried to find diversity between the universes. The fact that Jim is also a writer made things a lot easier because he could express exactly what he wanted. I just made pictures from the words he and Glen wrote.

"The most interesting challenge was creating what we called Universe A and C, or present time and the near future," Snyder says. "They were supposed to look exactly alike except for little subtle changes. The audience will see what appears to be the same scene twice. It's really two different scenes in two different locations. We've changed the vehicles, the advertising, the color palette and textures. It's very clever writing that allowed me to have fun.

"You always try to do something that's never been done before," Snyder laughs. "But, of course, there isn't anything that hasn't been done. So we tried to bring a diversity to the different universes and not compare ourselves to other films. The future Multiverse Agency is very Spartan and utilitarian. There's not a scratch on the floor, there's not any dust, it's perfectly clean. But the current day factory has a lot of texture and grease and dirt. The home that Gabe and T. K. live in is beautifully kept, but it's worn with love and age. Every location was approached on its own merits. "

Pre-production preparation also included designing many of the fight sequences. They were choreographed by world-renown fight director Corey Yuen (also known in China as Yuen Kwei. ) Because Yuen was in France overseeing the martial arts for "Kiss of the Dragon (2001)," he and his crew came to the United States to begin designing the scenes for "The One" a mere three weeks before cameras started to roll. Yuen's assistant fight director Jonathan Ke Quan and assistant fight coordinator David Lai acted as translators between the English speaking actors and his all-Chinese crew.

Early in his career as a stunt coordinator in China, Yuen worked on a picture with a similar premise - one actor playing dual roles. He was curious to see how the filmmakers approached this challenge and how today's technology would advance his own contribution to the film some twenty years later.

"This movie is a little different than many martial arts movies audiences have seen," says Yuen. "We tried to keep the wire work to a minimum. We also utilized more of Jet's martial arts ability because he's so good at it. The audience wants to see the way he fights. But when the director asks for spectacular moves because the characters are in a particular universe or because we have to magnify a character's power, strength and speed, the moves need to be more exaggerated and it's impossible for a human being to do, then we resorted to the wire technique to enhance that bit of action or to make it possible. But overall, we relied on Jet's own ability. It's very ballet-like. He is one of the greatest martial artists in the world. "

Jet Li and Yuen decided to use two distinctly different styles of fighting to discern between Li's characters. They selected Bagwa, a circular motion for the good Gabe and Shinyi, a straightforward punching attack for the evil Yulaw. "We wanted the audience to be able to clearly identify one particular style of fighting with the good guy and one with the villain," Yuen describes. "In Bagwa the fighter moves in a circle, which fit with Gabe. He is an ordinary man who is trying to find his center; he tries to maintain his calm throughout the story. In Shinyi, Yulaw is extremely motivated to achieve his goal of becoming 'The One' and he will do anything to achieve that. So he's the kind of person who does not care about anything else and attacks forward to obtain what he wants under any circumstance. He never moves backward. He fights in a straight line because he believes that's the shortest and the fastest distance between two points. We put these opposing styles together. It's very interesting to see how they come together. "

Sequences in which Jet Li is fighting himself required the skills of experienced stuntmen and martial artists Yong Guo Jian, Lin Feng and Sam Huang Ka. Li would first fight as Gabe, then change wardrobe and fight as Yulaw with his stunt doubles. The final battle between good and evil took the company four weeks to film.

Yuen and Li have worked together many times. Yuen has acted as both a martial arts action coordinator and as a director on several of Li's films. Their skills and time together makes for a seamless collaboration. "Jet is very smart with any kind of action," says Yuen. "When we discuss what we're doing Jet always offers suggestions. He's always looking to create a situation audiences haven't seen before. And if I suggest something new, he gets it instantly. He's very quick. "

Yuen and his staff not only were given the task of designing the fight sequences, they also acted as martial arts instructors for Delroy Lindo and Jason Statham who underwent intensive training.

"When we began training Delroy, Corey was worried that he might not be flexible or smooth enough because he's such a big guy," says Jonathan Ke Quan, Yuen's assistant fight director. "Delroy's 6'2" or something like that. We thought the kicks might be too much, but even on the first day he went full at it. After a week of training we realized how good he was and what an incredible attitude he has. It was really fun to work with him. "

"Delroy is very serious about everything he attempts," says Li. "We had a fight scene between his character and Yulaw. A stunt double could have done it, but Delroy didn't want that. He really wanted to fight himself and it was an intricate sequence for someone who just began training. He's a wonderful actor. "

"Jason had the same level of enthusiasm as Delroy," adds Wong. "He always wanted to do his own stunts, and we had to tell him, 'No, that's why we have stunt doubles, because we don't want you to get hurt. ' He was willing to do anything. We had to keep our eye on him," the director laughs.

Quan agrees. "At first we only taught Jason punches, but he kept after us, saying he wanted to learn Chinese Kung Fu. So Corey had him do spinning kicks and jump front kicks, and he was really good at it. "

When Yuen first got the job, he was excited at the prospect of working with a Chinese-American director. He also felt relieved because he was under the impression that he would be speaking Chinese with James Wong because Yuen spoke little to no English when filming began. "I thought, okay, I'm going to be able to communicate with him in Chinese," laughs Yuen. "And even though Jim understands a lot, he speaks very little. But it was wonderful working with him because he has so many great ideas, and even though his initial knowledge of martial arts was not big, he caught on immediately and was very clear about what he wanted. He was very specific about the kind of rhythm and mood he wanted to achieve. "

Yuen worked hand in hand with stunt coordinator/second unit director Gary Hymes. Hymes and his staff not only erected and oversaw the flying rigs for the wire work, they also supervised the many stunt sequences, some of which included martial arts.

"This film is a little bit different than most," Hymes explains. "I worked very closely Corey Yuen. Corey was wonderful in terms of looking for other input and we'd toss around ideas together. But I was amazed at what he came up with. He had some very creative and different types of fights that I hadn't seen in the past. We would look at what he put together and say, 'How can we enhance this?' We'd do that through our technology, using various types of wire gags, pneumatic ratchets, propane mortars and so forth. So it was a combination of east meets west. "

Hymes was particularly excited to take on the film when executive producer Lata Ryan asked him to come on board. "There are very few scripts like this one that you become excited about when you first read them," he says. "The action is a totally different type of action. It looked like an opportunity to break new ground and try a lot of different things. We've really pushed the envelope in every direction on this film.

"Given the nature of this film and the amount of wire work we did, it required a tremendous amount of preparation," he continues. "Whenever we fly people through the air, we use a lot of pneumatic devices and hydraulics. Rehearsals are essential not only for the best possible performance, but also to fine-tune the stunts. It also gives us an opportunity to show Jim ahead of time. We videotaped most of what we did which helped in that regard. This was probably the most rigging intensive film I've done since "Hook," in which we had quite a few people flying on wires and rigs, but I think this just might have surpassed that. "

In one sequence Yulaw is trying to elude the police as they are in hot pursuit. He leads them into oncoming traffic, and as they start gaining on him, he jumps across what is supposed to be a 30-foot gap over the Harbor Freeway. Hymes and his team did some rehearsals early in November to fine tune the action and to make sure the stunt looked believable. They used a crane and a pneumatic ratchet along with a deceleration device to fly one of Li's stunt doubles across an opening above the actual freeway.

"The freeway was moving," Hymes explains. "We didn't stop traffic for this sequence, but there was one lane that was a connector ramp directly below us, and we did stop traffic there given the requirements of Caltrans. Other than that, everyone was extremely cooperative and it went well. "

Principal photography commenced on January 29, 2001 at stages in Playa Vista, California. Locations used included a power plant in Redondo Beach where the crew spent nine weeks of night shooting, the Sybil Brand Institute in Monterey Park and the old Unocal Building which has been converted into a state-of-the-art studio facility now called the Los Angeles Center Stages. Other scenes were shot in Glendale, Torrance, Valley Village and downtown Los Angeles. Production designer David Snyder also created a vast set for the Stygian Penal Colony located in the Universe of Hades at Universal Studios.

"The great thing about a science fiction movie is that all the normal rules don't necessarily apply in terms of how things look," says director of photography Rob McLachlan. "It gives a cinematographer a lot of license in terms of how to shoot and more freedom to express yourself visually in terms of interpreting the story than you would in a normal drama where you're confined to familiar environments. We're going to places that no one has ever been before. There's no one to say, 'Well, all the lights look like this and all the people look like that, and everything is this color or that color. ' So it gives us a lot more leeway. The other great thing about futuristic locations is that, the variety and contrast within a film are exciting to play with. And because we used parallel universes, visually you want to give the audience some clue that they've gone somewhere else so it's not completely confusing. One of the ways that we did that was to give subtle hints with color and the design of the sets. David Snyder did a beautiful job of making some subtle differences between the different universes with his designs. We took that concept a few steps further with the color of the light we used. For instance, in the prison sequence that opens the film in what we called Universe A, or the penal colony, it is slightly futuristic and we used lavender gels that gave it a really intense color.

These gels are something fairly new on the market. Before they were created you could not really put this color on screen. It's a very compelling tone; it's very dark and moody. From there we move to the universe that is somewhat more familiar to us, that looks a lot closer to the one that we live in, and then there's another that is slightly different again. So it's given us a lot of room to play with different qualities of light, different colors of light, and so forth. When we're in the Multi-Verse, it's somewhat subdued. In post-production we pulled a little bit of the color out of it, so it's a bit more monochromatic, and that way we got a variety of looks. The big thing that we did in the in the universe that most of the film takes place in is make it a cool, not particularly hospitable world, with the exception of Gabe's house, which is the only place that's really warm and cozy and inviting. In the Happy Universe the whole world is very intense, with saturated color and late afternoon light. But all the rest of the environments that the characters find themselves in are not particularly inviting. "

As Yulaw's power increases, he becomes a sort of super man. He's faster and stronger and the filmmakers needed to find a way to convey this expansion of his powers on screen. "We decided to use a technique where Yulaw would look like a blur when he's moving at super speed," says Wong. "To do this we changed the perception of how we see ourselves. When he's moving fast, we are moving much slower. In other words, we tried to slow down the world as he goes speeding by. "

"I wanted to try and find a way to create within the camera an effect where Gabe and Yulaw looked like they were moving incredibly fast rather than using the conventional methods of slowing the camera down or computer graphics," says McLachlan. "I remembered some tests that I'd done a long time ago with strobe lights that were designed for photographing liquid. The technique has been used in very small amounts in TV commercials to freeze motion. The process gives you an incredibly sharp image because the exposure time of the strobe -- it's like the flash on your still camera -- pops at a very high rate of speed that arrests motion. What I also discovered was that if you combined the strobes with normal light it produced both an incredibly sharp image and a very blurred image. We took this concept one step further when we strung together thirty of these strobes, which has never been done before, and put them all together in a big line. This created the effect where Yulaw is trying to evade the police and is actually running so fast that he's passing cars driving down the street. I'm really excited that we were able do it because it is an incredibly difficult and labor intensive effect, but looks absolutely beautiful on screen. "

Coordinating the martial arts and stunts with the visual effects team's strategy was paramount once filming began. Visual effects supervisor Eric Durst and effects producer Susan Zwerman oversaw the arduous task of coordinating the many sequences. They turned to the visual effects gurus at Kleiser-Walscak for their assistance and expertise.

"The storyline required a number of different images that required different visual effects techniques," says Durst. "For instance, we needed to show how several characters travel through multiple universes as well as the physical changes that Jet's character goes through. In one universe he has powers that are beyond the scope of real people, speeds shift, time shifts, things like that require visual effects. In another sequence, the scope of the set expanded, so we use matte painting techniques. And then there is the universe where Jet confronts himself, which require another methodology. These scenes need to be credible and blend well so that they have impact on the story. "

In the final fight sequence the visual effects department first attempted face replacement using a mask on the stuntman while he was fighting, but challenges soon arose for the actors. "The mask was too much," says Yuen. "They cut holes for the eyes, but the stuntmen didn't have peripheral vision and they couldn't see up or down, only straight ahead. During a fight sequence, you have to be able to see where a kick is coming from to block it. We kept cutting the holes bigger and bigger," he laughs.

"The foundation for this technique is based on taking the photography and bringing it into the three-dimensional world of the computer," says Durst. "For example, the 3-D version of the mask that is placed on the actor as he jumps over the MRI machine has been tracked in the computer and is exactly the movement that occurred on stage. We can take this 3-D representation and project Jet's face onto it, thus having the right amount of shading and lighting, so we see his facial expressions. The image is then composited into the photography, which tracks the actor's performance and we see Jet in what appears to be real space and time.

"Since there are differences between Jet's face and the stunt double in the chin and cheeks," he continues. "We had to clean up those areas. We have to pay attention to dimples, highlighting of the eyes and make it all come together. "

"We did some visual effects tests prior to shooting," says Hymes. "We were on a sound stage shooting a sequence, I knew exactly every move and everything that took place. Then I saw it two months later, after all the visual effects were applied to it, and I kept watching, thinking, 'Was I there that day?' It was absolutely incredible. This new software and technology provides us with amazing possibilities with what we can accomplish. I think this film is going to be extraordinary. "

The filmmakers are quick to point out that although this movie employs techniques never seen before, most of the technological advancements are virtually imperceptible. "It's not 'Matrix, The (1999)'," advises producer Morgan. "I don't believe that audiences will know they're watching a process they haven't seen before. It's too subtle. But they will see things they don't expect, plot points not normally seen in action movies and time changes that might make them think that the projectionist put the wrong reel up in the wrong order. "

"Anyone who is ready for an exciting, fast-paced, action packed thriller is going to enjoy this movie," says Wong. "It starts off like a rocket and just keeps going. It's a lot of fun without being too dark or heavy. We certainly enjoyed making it. "