For years, Robert Rodriguez dreamed of making a family movie that would take place inside the virtual world of a video game, a world that excited him because anything can happen there, because speed, colour, strength and the intensity of adventure can be magnified beyond all human proportions.  But it wasn't until the director began thinking about his next Spy Kids movie that he realised this was a perfect mission for underage agents to play the toughest video game ever invented for the highest of stakes:  saving the youth of the world. 

Says Rodriguez:  "For a long time, I had plans for a family science fiction movie about siblings who get stuck inside a video game and I wanted it to be in 3-D.  I liked the idea of the audience getting totally immersed in this visually exciting world, having to duck and shift in their seats to avoid being hit by flying objects. It soon occurred to me that this was the perfect concept for the third Spy Kids movie. It's totally different from the first two movies, yet takes the characters everyone already knows somewhere completely new and has lots of fun surprises for the audience.  And because the Spy Kids are immersed in this digitally animated world, it raises the bar on visual excitement and thrills. I realised this wouldn't really be like making a sequel.  It would be a completely fresh and exciting challenge for everyone involved.

Rodriguez had played plenty of video games in his life, beginning with PONG in the 70's and now with his own children. But as he started writing the script, he began to envision a kind of "ultimate video game," one that was faster, wilder and more complicated than any he'd ever encountered. This became "Game Over," the new software designed by The Toymaker to draw kids into his trap with irresistibly sweet graphics and a cool multi-level design. 

"The idea was strong, and I quickly realised I was going to have to invent some really wild new levels in order to live up to the potential this story was offering. I also wanted the video game in the movie to be a combination of different game genres. One level would be spooky and full of stealth, another level would have battling mech styled robots, another level would be a zany and colorful Ninentendo64-type world with giant Toads on pogo sticks whipping their tongues at the characters and the audience. Others would be more extreme sports type levels with unicycle Road Warrior-style racing, and Lava Surfing," he says.  "The idea was to create one exciting set piece after another, and have each level get more complex visually as you progressed through the game and became more involved in the characters. I wanted to create a game that I'd like to play with my own kids, but also one we'd really love the chance to go inside. And of course each challenge in the game had to be conducive to hurling objects the audience must dodge. There was certainly a lot to think about, and an enormous amount of condensed design work."

Another inspiration for Rodriguez was his life-long love affair with 3D.  He wanted to bring the excitement of sharing this kind of movie-going event to a new generation that has never experienced the fun of wearing 3D glasses with their friends and family. Rodriguez was raised on such 3D classics as "House of Wax" and Hitchcock's "Dial M for Murder," but for SPY KIDS 3D, he wanted to bring the latest computer and camera technology to the party. Using a high-definition video camera created by James Cameron and Pace Technologies for the acclaimed 3D documentary "Ghosts of the Abyss," Rodriguez also designed rigs to re-invigorate and simplify the whole 3D process. Along the way, he also sketched, invented and oversaw the digital creation of some of his most sophisticated CG characters, creatures and vehicles to date. 

In writing the script, Rodriguez was influenced by the idea that the Spy Kids, Juni and Carmen, are getting older, stronger and savvier - and more capable of serious espionage action.  Accordingly, he upped the action, and the stakes, in this movie.  "Juni and Carmen have become a lot more confident in this story," Rodriguez notes.  "And so too have Daryl Sabara and Alexa Vega as actors.  Daryl and Alexa do a lot of things in this movie that would have been impossible in the first two.  But by gradually facing and conquering the challenges inherent in the past movies, they were very prepared for this movie.

The writer/director also created the most complex and threatening villain the Spy Kids have yet faced:  The Toymaker, a computer mastermind and brilliant inventor with multiple personalities. "I think I can most relate to the Toymaker because in some ways he is trapped in his own imagination. He has all these different voices going on inside his head, these split personalities that are always arguing with one another. On the set, I also have to split myself up - I'm the guy who does lighting, sets up the shots, designs the production and costumes, wrestles with the 3D, while writing (and rewriting) and directing. And none of those different people are ever in complete agreement with each other. So I drew a bit from personal experience in creating him, because I know how jumbled things can get when you're trying to create something big while coordinating different parts of your personality! And at night, that's when the voices would really start talking. I don't get much sleep."

A Quick History of 3D and Where The Spy Kids Take It
It has always been a dream of mankind to be able to simulate the real world in all its wild textures, shapes and depth of motion. Long before the Spy Kids entered the Third Dimension, scientists, artists, photographers and filmmakers had been playing with ways to make the human eye see moving images in a completely life-like fashion, full of palpable structure and form, instead of as a flat canvas or screen.

As early as ancient Rome, artists experimented with techniques to make paintings "pop" and tease the eye with extra depth and dimension.  Then, in 1838, came a breakthrough.  Physicist Charles Wheatstone created the world's first stereoscopic viewer, allowing anyone to see pictures in multiple dimensions.  Wheatstone based his invention on the scientific reality that our left eye and our right eye see the world from slightly different angles.  When we look at an object, the brain magically fuses the two images into one, allowing the viewer to understand depth and distance. 

Taking that idea one step further, Wheatstone created a special viewer that could display two different pictures from two different angles simultaneously - one image to the right eye and one image to the left.  When viewed together, the two pictures created a "stereo" effect that gave the resulting image a greater sense of dimension. It was as if you were no longer looking AT a picture, but right through it!  In 1854, the London Stereoscopic Company was formed, and their breathtaking portraits of Niagara Falls and New York City became inspiration to millions.

In the 20^th century, filmmakers became curious about the potential for using stereoscopic principles to make movies more visceral and fantastical. By creating a camera with two lenses about the same distance apart as human eyes - known as the interocular distance, which is about 2.5 inches -- early 3D filmmakers were able to capture two images simultaneously.  The only problem was that during projection, the effect was as if the audience was seeing double.  This was solved by creating anaglyphic glasses, or glasses with one red and one blue lens.  When a person wears anaglyphic glasses, each lens filters out the opposing image, and the brain then fuses the two.  The result is the singular sensation that you're experiencing a movie in three dimensions!

Once developed, 3D caused great excitement in Hollywood, both with directors and audiences.  In the 1950s, moviegoers flocked to numerous three-dimensional features, often horror movies, such as "Bwana Devil" and "Creature From the Black Lagoon."  In fact at the height of 3D production, some 30 3D movies were released each year! For much of that time, the application of 3D was limited by technology, and the filmmaking techniques of the day could not overcome the headaches and eyestrain 3D could cause.  Even so, filmmakers continued to recognise the potential fun and excitement of the format.  In the 80s, 3D was added to give new life to such blockbuster franchises as "Jaws" and "Friday the 13^th." 

More recently, with skyrocketing advances in camera engineering, optical technology and computer-generated special effects - as well as the race to create a true virtual reality experience for audiences - 3D has experienced the start of a new renaissance.  Innovative filmmakers are just beginning to explore how far the new technology can go.

When Robert Rodriguez decided to make the third SPY KIDS installment a 3D experience, his first thought was that he'd have to start by inventing an entirely new 3D camera from scratch - one that would use the high-definition digital video that gives him the stylish flexibility that has become his trademark.  To his astonishment, Rodriguez then discovered that a much better version of the camera he was designing already existed!

In fact, director James Cameron had commissioned the creation of just such a versatile camera for his groundbreaking 3D documentary "Ghosts of the Abyss." Cameron's camera essentially fused two high-definition video lenses (separated by the interocular distance of 2.5 inches) together into one unit. Although never used for a fictional film before, let alone a family film, the camera offered a lot of what Rodriguez had dreamed about, and more.  The camera was even designed with a unique ability to cross its lenses, rather like human eyes crossing, in order to reduce eyestrain for the 3D viewer.  Most of all, it was an extremely adaptable system.  "Leave it to Jim to go where no one has gone before in designing this amazing new system. Once you've shot your movie with the two cameras, you can release it a number of ways. The same movie can then be used in IMAX, at a theme park, in theaters with anaglyph 3D glasses, or even on a flat television screen without the 3D," says Rodriguez.  "You have all the options."

"The first concern on any 3D project is the fact that you're flying blind," Rodriguez says.  "As a filmmaker you are unable to see what you are capturing on the set, which is crucial to capturing great 3D. That's why other 3D movies are so static. They had to lock down the cameras, choose a convergence point, and then let it ride. A lot of 3D movies rarely work because of the 'shoot it blind' way of working. Not so with this new system. Because we were shooting in high definition, we were able to install a unique monitoring system at our Austin, Texas studio: a four-foot by three-foot high-definition 3D projection screen that allowed us to see exactly what the finished image would look like in astonishing clarity - as long as we were wearing our 3D glasses!"  This set-up allowed Rodriguez to focus on two of the most essential elements of 3D filmmaking:  convergence and focus.  Convergence refers to the point of focus at which two images cross.  By using convergence, the filmmaker can determine if an object will appear to be behind the screen, in front of the screen, or somewhere in between. This was essential to creating the sensation of flying Spy Kids, floating robot heads, hurtling toads, spewing lava balls, zooming high-speed vehicles and glowing staffs that pierce right through the screen.
The challenge had the special kick of an adventure for Rodriguez.  "Filmmaking is already a visual medium, but doing it in three dimensions only makes it that much more exciting," says Rodriguez.  "I think making a 2D movie is going to feel a little too easy after this, because 3D is about envisioning a whole world, full of color and depth.  You have to approach everything in a new way when you're not just looking at a flat image in front of you. I had to rethink the way I would shoot and light, the production design, even the way actors move and talk, in order to make it all work in three dimensions - and this made the emphasis on the visual elements stronger throughout the film."

He adds:  "The hardest part was probably for the actors who had to act out all this incredible action entirely in front of a green screen.  They had no walls, no sets, not even props to help them - since everything had to look like it was set in a video game, even the props themselves needed to be computer generated. If they were lucky I might be able to give them a thumbnail sketch but a lot of it was just done out of sheer imagination. I wanted the moviemaking process on this to be as free as it had been on my earlier movies that had no effects. Knowing a lot about effects, and what was possible, we were able to really fly free everyday. I improvised a lot with the actors.  The actors could try out different ideas spontaneously as we were shooting - and they did their part by coming up with all kinds of fun concepts on the spot." 

Shooting in 3D further spurred Rodriguez to consider all kinds of visual elements in greater detail - especially the use of colour and perspective.  Early 3D effects from the 1950s appeared in black and white.  Polychromatic 3D images are still a new frontier, and require extreme care in colour-correction. Rodriguez used real-time colour correction that allowed him to correct each frame's colours to his eye's satisfaction instantly.  But one thing Rodriguez had to get used to was the idea that the use of his absolute favourite design colour - primary red - had to be limited (no red light gets through the blue lens of the anaglyphic glasses).  "To me red is a colour that just pops out and I really like to use a lot of it, but when you're wearing anaglyphic glasses, you can't see true red, so I had to start thinking differently.  I learned to like purples," he notes.  "Eventually, I discovered so much about how different shapes and colours would appear in 3D that I realised I was going to have to design a lot of the costumes myself, it was not only a lot faster for me than having to explain it all to someone else, it was also probably the most fun job on the set."

As for depth, Rodriguez wanted to avoid the staged look that has sometimes plagued 3D productions of the past and bring out richer layers of texture.

All along, Rodriguez wanted to avoid only one thing: predictability.  "I think a lot of the fun of what we've created in the film is through the set-up of the different 3D gags.  In previous 3D movies, you might have nine or ten good 3D gags, but this movie has hundreds and you can't always see them coming," he says.  "We started from the rule that anything is possible inside a video game so anything could happen on the screen. 3D with anaglyphic glasses works fantastically well with computer generated images, so we were able to raise the bar even further on new thrills."

Helping Rodriguez to create this chaotic, anything-can-and-and-will happen world were his crack team of special effects specialists, who were at the ready to sketch, composite and render on demand. Since you can't shoot computer animation with a 3D camera, the effects team solved the problem by rendering each shot twice:  the first time as seen by the right eye, and the second time as seen by the left.  The computer then interwove the two images and voila: a 3-dimensional virtual reality world was created. Rodriguez notes:  "One of the great things about having my own effects company is that I could work with the technical people to develop effects on the fly, rather than having to wait months to try out ideas.  I've realized in making the SPY KIDS films that the more versed you are in the technical aspects of moviemaking, especially effects, the more it allows you as a director to be free creatively and push the envelope."

Perhaps just as astonishing as the effects Rodriguez and crew created is how fast they did it - cramming into only a few months a pioneering technological production.  "For me, making this film was a bit like being thrown into the most frantic, hectic, challenging video game there is," says Rodriguez.  "But it was by far the most fun I've ever had. There's also a creative bonus to moving fast. You tend not to over think things, and you head straight towards the ideas that really work, and discard the rest. It's a very efficient way to work, one that allows complete creative freedom because you're also controlling the budget by doing it that way. Lower budgets mean total creative freedom, which is ultimately what you want as an artist."