Whether it's playing Facebook founder Mark Zuckerberg or his recent role in "The End of the Tour," actor Jesse Eisenberg has found a way to bring life and humor to real-life situations.

In "American Ultra," Eisenberg is transformed into an unlikely action star as Mike Howell, a seemingly normal slacker with an affinity for weed from small-town West Virginia, He works as a store clerk but is, in fact, a sleeper agent for the CIA. It's such a different role, some might wonder how it landed on Eisenberg's doorstep.

"Usually I have that thought exclusively, even if it was the story of my life. That's just my natural reaction," Eisenberg joked with amNewYork recently. "The main thing is, 'Can I do this well? Do I understand what this is? and, does this feel like a real person that could exist outside of this movie?' because those are the characters that are fun to play.

Eisenberg said he had "great affection" for his character.

"He just wants to do good," he said. "He wants to propose to his girlfriend and draw his cartoons. He has no lofty ambitions, and when the CIA is coming to wipe him out, he just wants to survive and save his girlfriend."

That girlfriend, Phoebe, is played by Kristen Stewart, who Eisenberg co-starred with in "Adventureland." Woody Allen liked them so much in Greg Mottola's 2009 comedy that he cast them together in his next film, due next summer.

"The goal for actors is to create some sort of emotional realism in these fictional circumstances," Eisenberg says about the pairing. "If you're doing a movie like 'American Ultra,' it's important to remember somewhere in the back of your mind it's OK to be funny.

"The more realistically we portray our characters, the more funny it would be because what's funny is the juxtaposition of our characters in this absurd, terrifying situation," he continued. "It always seems to me that it's probably a good thing to acknowledge the irony of life."