The D23 Disney Expo's 700-seat Walt Disney Studios Theater was packed last Friday for the "Tron Legacy" panel, presented by producer Sean Bailey and original "Tron" director Steven Lisberger.After Lisberger's retelling of some behind-the-scenes details on the making of the original "Tron," Bailey explained the impact of the original film on him. "It left an indelible impression and then went on to [cause me to] spend too many quarters on the [video] game. My dad was a scientist so I was kind of fascinated and I think I had some very small notion of what these guys were up to and was fascinated by it. Going into a computer, what a radical, huge idea. 'Tron' kind of became a divide between the analog and the digital world."With respect to "Tron Legacy," Bailey explained, "I got involved with the movie five years ago or so. Shortly thereafter, we found a young filmmaker named Joe Kosinski, and Joe made a couple of very smart decisions. He really respected the work of [designer] Mobius [from the original 'Tron'] and he said who are those folks out there today? Immediately, we kind of commenced a search for whoever was the most exciting artist, irrespective of whether they were in the movie business or not. So we brought together a guy named Daniel Simon -- who is one of the most bleeding edge artists from Germany -- and a guy named Vyle Levy, an architecture guy, [to work on 'Legacy.']"Joe told them, there is an incredible design in the original 'Tron.' Look at the light cycle, look at the Recognizer. If you look at a Porsche 911 from 1968 and you look at one now, you can tell they are the same vehicle. There's no reason to mess with the fundamental DNA of the design. But how do we take it and evolve it? Our understanding was that the original design of the light cycle was that it had an exposed rider, for example. They just didn't have the computer capability to render it. So we sat down, all of us, and said that's what we're doing."Regarding the story of "Tron Legacy" and its nature as a sequel, Bailey said, "We all sat down and said let's make this a stand-alone sequel. Meaning the movie can exist on its own, but we're going to accept that the events of [the original 'Tron'] happened; that Kevin Flynn went in, battled the MCP, came out, NCOM exists. We first started by building all the intervening mythology. So this movie takes place in 2010, and deals with the son of Kevin Flynn, Sam Flynn, and events that have significantly changed both in the system and outside, from what we learned in '82. I'm excited by the choice. This is a continuation of the narrative."

As to what the "System" is in "Legacy," Bailey explained, "A choice we made, sort of collectively, is that this isn't a movie about the Internet. We're going to say that this System of Tron, this universe that Stephen created, existed and evolved on its own, sort of like the Galapagos Islands. So this is a universe unto itself, we're going into another world. This isn't a movie about the World Wide Web at all." Regarding the return of Jeff Bridges to the universe of "Tron," Bailey focused on the critical nature of his return, stating, "I don't know how you just read a script like 'Tron' and say, 'Okay let's go hire a director!' We think you have to do visual R&D as well. And so we started while we were building the story -- we built the two in concert. And we built that storyboard and concept art and brought Jeff in early and said, 'We don't have a script. We want to kind of do this idea of a sequel. You're Kevin Flynn, and also you're going to play another guy in the movie too.' So Jeff is in the movie in two parts. And we said, 'We're going to go shoot this, and we need you to be in it.' "Jeff, from our recent experience with him, is the kind of guy who wants to push it. He's ambitious in his acting choices, and he basically said, 'You're going to go try stuff that's never been done before. I'm in.'" On the visual look of "Tron Legacy," Bailey harkened back to an early quote from the director, Joe Kosinski, who said, "Steven and his team, because of the times, said we're forced to use practical tools to basically create a world that looks digital. What I'm going to do is use digital tools to create a world that looks like a photograph."Bailey then introduced a series of concept art slides, saying the pictures show a dark world with lots of atmosphere, tactile environments, and a focus on physics. He explained the film's attention to detail. "A lot of people thought we would use all-digital environments. There is a lot of digital work, but what I think is going to shock a lot of people is that we built a lot of Tron City, we built a lot of these environments, we built the Tron suits that are actually practically lit," Bailey said. "I think a lot of people are surprised by how much we actually went out there and made."The slides included: The Recognizer, Tron City, the Solar Sailor, various landscapes and set pieces; the Light Runner, and the Arena, which Bailey said is "Where we play an update of the disc game. The disc game is kind of happening in a gladiatorial bloodthirsty crowd. The boards move together in real time as people advance. We brought in some athletes that we discovered who practice this sport called loop kicking. It's kind of a cross between par core and martial arts. These guys are using no wires. All these guys are non-traditional stunt men."The environment of many of the slides indicated The System has changed since the original "Tron." "There is still the sleek Tron city, but there are also now rough outlands. It's more rugged," said Bailey.

More than one version of the updated Light Cycles were also presented. Bailey discussed two versions in the movie, stating that the updated Light Cycle was designed by Daniel Simon and Kosinski, and there is also a 1989 version of the cycle, as the movie will at times go back in time to points between 1982 to 2010.Bailey discussed the impact of changes on the population of The System universe, "[We thought about] Moore's law of speed, how did the world grow, how did people in the world grow and evolve. It's a massive universe, with all kinds of factions and entities and villains."Asked how the mythology of "Legacy" was built the work of writers Edward Kitsis and Adam Horowitz, (who also work on the "Lost" television show), Bailey said, "Those guys are obviously great at that. We sort of built the story nontraditionally. Steve, Joe, myself, and Eddie and Adam from 'Lost' sat together in rooms for hours and hours, just Diet Coke and pizza boxes, and went to town, thinking about what was exciting about the plot and the story and what the characters were about."On the role that new technologies played in the making of "Tron Legacy," Bailey said, "The 'Benjamin Button' technology is one of them, and we use a version of it in our movie. We thought, how do we use these new technologies so they aren't just bells and whistles, but to create visuals we've never seen before? How can we make scenes and create stories that no one has been able to do? Before, you couldn't have Jeff Bridges in the movie twice, at two different ages, seamlessly and realistically. "I think we can also do some things with story, because of the technology, that nobody else can do. We shot it all in 3D, so all the CG work will be 3D as well. We have to create a movie screen that looks unlike any other. We really feel we owe a few things [to the audience] here. We owe Jeff Bridges, we owe a screen that looks unlike any other movie, and we owe the Light Cycle. "Bailey explained that there is a relationship between the real world events portrayed in "Legacy" and the events that occur in universe of the System. "Something very big happened in our world in 1989, and Kevin Flynn disappeared. And that event, which you will learn in the movie, is tied to something that happened in the System. There is a correlation. We created a mythology for '82 to 2010 in this world, and '82 and 2010 in that world." As for the role of Jeff Bridges in the new film, Bailey said, "He's in the movie a lot. He's a significant, significant character."The panel closed with a 3D version of the "Tron Legacy" preview clip, followed by a digitally re-mastered viewing of the original "Tron" film."Tron Legacy" is slated for release on December 17, 2010.