Leighton Meester explains police run-in

The 24-year-old actress stars in the upcoming gritty drama, a movie which tells the tale of a college student who gets assigned a dorm room with a dangerous new roommate.

Leighton had to shoot some rather violent scenes for the film, and one day when she was leaving set – still covered in fake blood from work - the actress was stopped by police in Los Angeles for driving too fast.

"There's a final scene where we have a little catfight...well, not little," Leighton told E! Online at a special screening of the movie. "So I'm a little battered. I was on my way home and I was on the freeway and I was going a little fast and I got pulled over."

Leighton instantly regretted not cleaning herself up after filming, especially when the police officers mistook the red make-up for genuine blood. The star complied with police checks, and admits she didn’t feel in a healthy mental state at all after shooting such horrific scenes.

"As I was getting pulled over, I was like 'I knew this was going to happen. I should have washed this off'," recalled the star. "I was just in a rush to get home. They thought it was real and they took me out of the car and did a little sobriety test to make sure I was OK. And they said I wasn't, which was funny, because I really wasn't. I was totally deranged from the movie."

Leighton found it funny how the police were intrigued by her fake blood, and were keen to find out more about the movie. The beauty also chuckled as she remembered the officers asking her about Gossip Girl – the US teen drama where she shot to fame playing Blair Waldorf.

"Then they were like 'Well when does the movie come out? When can we see it? And...aren't you on that show Gossip Girl?'" Leighton laughed.