After Liam Neeson launched himself as an action star at age 56 with 'Taken' (2008), middle-aged actors are showing up in cinemas to prove that they can take it too. Now with 'The Gunman' (directed by Taken's Pierre Morel), it's Sean Penn's turn. This seems like an unlikely role for the double Oscar winner, but he says he never thinks about his career when he takes on a job.

Sean Penn in 'The Gunman'
Sean Penn in 'The Gunman'

"I'm more of a movie by movie person," he said. "I take each one as its own animal. Harrison Ford made a whole career out of this stuff. So it's not a new trend - it's what I call 'geri-action'! Many of these are 'wink at the audience' kinds of movies, but 'The Gunman' was more a straight line. There were consequences to the violence - that appealed to me more."

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As usual, Penn provided considerable input to the project by preparing for the role, and he is credited as both producer and writer. "While Pierre was busy choosing location and actors," he explained, "I was busy bringing some authenticity to some of the NGO scenes and working with consultants on the military side. I have spent time on projects working with special forces and private contractors on my other jobs."

Watch The Trailer For 'The Gunman' Here:

But he knew that playing a tough guy would require extra training. "You know, there were a lot of preparations to this movie," he said. "And by the time I got there, there was a lot of movement. I mean there was an extraordinary achy body by the end of the film!"

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Penn hopes his input into the script will keep the movie from being seen as just a mindless revenge thriller. "If someone younger sees the movie, and then if there is a report on the Congo or on some similar situation with exploited resources and with people paying the price for it, maybe their ears will perk up," he said. "There is no aspiration to change the world with a picture, but I though there was a good real-world refection in there."