Jessica calls the film is a mix of genres: Gangster meets Western meets Love Story. It's set in the time of Prohibition. And history buff Jessica loved being able to take a step back in time.
"I love researching," says Jessica. "When I get a role that's one of the very first things I do. I just want to fill myself up with knowledge of what the character might have come from. Not just even reading about the history of the time, which of course I do, but I also love learning about the music of the time, listening to that; thinking of the food of the time; what someone would have done for fun."
With "Lawless," the fun for Jessica came from working with an ensemble cast that includes Shia LaBeouf, Tom Hardy, Gary Oldman and Guy Pearce.
"I geek out all the time because I'm so excited to work with people and that's what it was like for me on this film," says Jessica.
"Lawless" was a fairly testosterone-driven set, one that had producer Lucy Fisher comparing Jessica and her male co-stars to Peter Pan's Wendy and the Lost Boys.
"They were always roughhousing and playing around and sometimes I would get involved, but for the most part, 'Boys calm down, now's time to work, we all love each other, let's go back to work,'" said Jessica. "They treated me very special. They were always such gentlemen around me."
Much of "Lawless" was shot on location in a small town in Georgia. Jessica says for fun they'd all go to Wal-Mart and buy supplies for their very competitive game nights.
She said she also tried moonshine -- and is not a fan.
"Lawless" is in theaters Wednesday.