SAN FRANCISCO (KPIX) — A new Will Smith movie coming to theaters Friday night uses groundbreaking technology to turn the actor into a younger digital version of himself.

Smith plays two characters in his new action film "Gemini Man," portraying an elite assassin who goes to war with himself and a much younger assassin.

"It was such a crazy thing when I first saw those initial images, because the images weren't there on set during the film. So it was probably eight months and then I saw the first images. That first side-by-side, it is just magical what we can do with technology," said Smith.

That cutting edge technology is 3D filmmaking. It transformed the 51-year-old actor into his 23-year-old self, thanks to the work of 500 visual engineers at Weta Digital, a company based in New Zealand.

The work was intense; "Gemini Man" took two years to make.

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