Watch Woody Harrelson, Ben Foster Horse Around About ‘Rampart’ (Video)

Harrelson admitted that he was in "a state of paranoia" during filming the movie

Oren Moverman's crime drama "Rampart" is a gritty movie centered on an L.A. cop "doing bad things to bad people," the director told TheWrap's Sharon Waxman Monday night in a video interview following a Q&A at the Landmark Theater.

But he, and co-stars Woody Harrelson (the bad cop in question), Ben Foster and Brie Larson couldn't stop goofing around after answering audience questions at TheWrap Awards Screening Series. 

Also read: Woody Harrelson Cozied Up to Cops — and Shed a Tear — During 'Rampart' Shoot

They turned dead serious, however, talking about Harrelson's work in the movie.

The actor said playing "Date Rape" Dave Brown was a good challenge for "a lazy son of a bitch" like him.

"On the other hand," he admitted to TheWrap's Editor-in-Chief Sharon Waxman, "I felt like I was in a state of paranoia, and everything around me was dissolving, and was putting everything precious to me at risk.

"And that wasn't the most pleasant feeling," he said.  "But when we did finally wrap that was a very satisfying day."