Kirsten Dunst and Wagner Moura immersed themselves in the world of conflict journalism to prepare for their roles in "Civil War," a gripping thriller set in a near-future America on the brink of collapse.

The film follows fictional Reuters photographer Lee (Dunst) and reporter Joel (Moura) as they race against time to reach Washington before it falls to rebel forces.

British filmmaker Alex Garland, who wrote and directed "Civil War," explained in an interview, "Something sad and dangerous has happened in journalism. The reason I put them at the heart of the film is that there are really good journalists out there doing good work. They don't have traction in the way they used to have," he said, citing undermining from politicians, social media, and biased news outlets. "I thought, 'well, I'll do something oppositional to that.'"

For Brazilian actor Moura, known for his role as Pablo Escobar in the Netflix series "Narcos," journalism has a crucial role in fighting societal polarization.

"People get information from social media and all the fake news and bubbles. Progressives only read progressive things, and conservatives are the same ... the role of the journalist in the world, I think, is very, very important," he said.

To prepare for his role, Moura sought to understand how reporters reacted in the field.

"To be in the field, in a war zone, is a whole other thing, so mostly what I wanted to know was not even intellectually how they did their job but what did they feel when they were in a war zone."

The cast watched a documentary about late Sunday Times journalist Marie Colvin, who was killed in Syria in 2012, as part of their preparation, said Hollywood veteran Dunst.

"The camaraderie of them under those circumstances was the most heartbreaking and beautiful thing that I'd seen," she said.

"What they feel is exactly what we wanted to capture."