As told by National Lampoon:
We enter the green screen set of Revenge of the Sith. I watch as George Lucas takes control. Stars Hayden Christiansen and Natalie Portman are both suspended twenty feet over the floor in hydraulic harnesses, their limbs clamped to their sides.
Both wear skin-tight green body suits that blend with the green background, with orange tennis balls glued to their bodies in a grid. Though the set is completely bare, I can sense the possibilities. In post-production, everything green will be replaced with the fruits of Lucas’s imagination, brought to reality through digital effects. I take a seat and watch the magic happen.
“Squint!” Lucas screams into a boom mic. “We’re animating your bodies to walk toward each other!” Green mechanical arms push the two actors together. Portman begins to twitch from the pressure of the clamps.
“Don’t move your limbs!” Lucas directs. “You’ll disrupt the motion tracking! Act with your faces! No, not your mouths! We’re doing CGI mouths. Just your eyes. Your other eye! Now squint! You’re in love! Squint like it!”
The director sakes a seat attached to a camera rig. “Here comes the wompherder! You’re running now! Your bodies are animated to be running! You’re in terror! Squint in terror! NOT WITH THAT EYE!”
The hydraulic arm jerks Hayden suddenly upward by six feet, contorting his spine visibly. Several members of the crew get queasy and run from the room.
“Ooooo! Now Anakin is riding the wompherder! Go Anakin! Squint, Natalie! Squint in admiration! No, not that much!”
The mechanism then moves the actors so they are horizontal to each other, the blue-clad Hayden on top of the blue-clad Natalie. “Now you’re going to make love to her, Anakin!” bellows Lucas. “This is the big conception scene! You’re making a Luke!”
The hydraulic arm attached to Hayden’s hips begins gently thrusting him back and forth into Natalie’s crotch. “Good! Good! Keep going! Cut!”
Man, this is great stuff. :)