"We started Benjamin Button in the mid-'90s with Ron Howard, but back then we considered it impossible," says Digital Domain's Ed Ulbrich, who was vfx executive producer on the picture. "The technology was like science fiction."

Once they got to work on the picture for real about four years ago, Digital Domain's vfx team discovered there were no off-the-shelf technologies that could do what they needed. Only a series of improvisations and discoveries let them cobble together a pipeline that somehow made it all work.

A key creative challenge, says Ulbrich, was "When the star of the movie is going to be a global, iconic actor, and you're telling the story of the character's life, it's really disruptive to the story handing off to a series of different actors." So it would be up to the visual effects team to turn the star into a wizened young boy who'd youthen through the picture.

In 2004, after the project returned to DD with David Fincher attached as director, they were able to do a test that satisfied Warner Bros. and Paramount, but the process showed DD something ominous, Ulbrich says: Existing performance-capture systems weren't up to what they needed. They could capture an actor's facial movements, but not a close likeness.

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