When you have been one of the biggest box office attractions in the past few decades like Will Smith has, a natural thought is how great it would be if there were more than one of him. That finally happens through the cutting edge technology used in the new feature film “Gemini Man.” 

The 51-year-old Smith plays burned-out elite assassin Henry Brogan, who has grown tired of death and turns in his retirement papers. The problem is the super-secret organization he works for has a terminal plan for ending a career and sends a 24-year-old who happens to be his clone to kill him.

It took 10 years from the initial script writing to get to the point where technology allowed director Ang Lee to make the movie with a completely computer-generated version of the younger Smith to act opposite the real Smith. It is a giant step forward from the computer magic used in Lee’s “Life of Pi.”

Smith’s preparation to play the role meant uncomfortable sessions with Lee where they watched Smith’s past acting efforts in “The Fresh Prince of Bel-Air,” “Bad Boys,” “Independence Day,” “Six Degrees of Separation” and “Men in Black.” Lee would meticulously point out things the younger Smith did that would work for the movie and things to avoid.

“We created a language of my old characters and the moments of what he was trying to capture. Before you learn how to act, there is a powerful thing from not knowing, and it is really difficult to recapture that not knowing,” Smith says. “We found some of those moments in my early work. It was almost like learning how to do bad acting.”

Once he had the right approach to portraying his younger self, Smith then faced the challenge of playing the two roles. The 51-year-old version was no problem, but in scenes with the younger character, Smith wore a huge brace on his head so cameras could capture the performance. Smith praises Lee for making sure there was time between playing the two characters so he wasn’t being jerked rapidly.

Smith was most impressed with how the younger version of himself has “youthful eyes.”

“You can’t fake innocence,” Smith says. “As a young actor, it’s easier to player older. But it is nearly impossible to play younger because once you know some stuff, it’s in your eyes. It’s in your cells. Once you have had sex, you walk different. It’s in your back.”

“Gemini Man” fits with the science fiction roles Smith likes to play. The genre often allows for the examination of huge issues, as in this case, with cloning. The older Brogen became a killing machine because of the tough childhood he lived, while the younger version ended up at the same point despite growing up in a loving environment. It is the debate between which is more important, nature or nurture.

“I loved the philosophical idea that we all plant the seeds of our own destruction,” Smith says. “We are our own worst enemies. We make choices and decisions in our lives that set things in motion that we can’t blame other people for. I thought this was a clever way to say we are the architects of our own rise or fall.

“There’s a phrase I heard the other day called ‘poison honey.’ We reach for poison honey a lot to overcome our pain and suffering. When I think about cloning, it’s one of those scientific reaches that ultimately pans out to be poison honey. It will be a reach that potentially comes back to bite humanity in way we are not considering fully.”

The idea that if given the chance to talk to your younger self, the conversation would be full of words of wisdom garnered through years of living life.

Smith has a different take on what he would do if he could sit down with himself as a young man.

“My younger self was wildly and insanely aggressive,” Smith says. “I was naïve and ambitious and aggressive. There is a power to naiveté that I am actually trying to get back into my life again. So, I would be asking my 23-year-old self for advice because he made some good decisions. He made some good calls. In the last few years I have been feeling trapped by the success I have had and the decisions and choices I have been able to make have been smaller trying to protect Will Smith.”

If you go

GEMINI MAN

PG-13, 117 minutes

Playing at Niantic, Mystic Luxury Cinemas, Waterford, Stonington, Westbrook, Lisbon