Leighton Meester arrives at the Golden Globe Awards Sunday, Jan. 16, in Beverly Hills, Calif. (MATT SAYLES/ The Associated Press)

Hitting almost too close to home, the new college based thriller “The Roommate,” features Leighton Meester as an over-medicated, delusional, roommate who falls off the deep end during her first semester away from home.

The film revolves around two roommates Sara (Minka Kelley) and Rebecca (Leighton Meester) and the adjustments the two have to make when it comes to living with a complete stranger. Much to Sara’s demise, Rebecca isn’t who she makes herself out to be. Plagued with physiological delusions, Rebecca’s obsession with her roommate drives her to commit acts of violence that she deems as rational.

Meester, who has never played the role of a villain before, thoroughly researched physiological disorders, in hopes of embodying her character as precisely as she could.

“I had the opportunity to really prepare for this, and got a lot of great psychology books and information on delusion and metal disorder,” Meester said. “I also had the chance to speak with many different psychiatrist about the disorder and get all kinds of information.”

Comparing “The Roomate,” to other great films thrillers centered around a deranged leading female like “Fatal Attraction” and “Single White Female,” Meester went to new depths to stay devoted to her character.

“During filming I did my best to maintain my character,” Meester said. “I was really lucky because all I had to do was work on this movie every day. I didn’t have any other obligations at the time, so I got to be really involved and focused.”

Being so committed to the role had both its advantages and disadvantages for Meester. Claiming to have a “firm grip on reality,” Meester admits to sometimes being too involved in her character.

“I’m weird and crazy like anybody else but this person, she really doesn’t have control of her mind,” Meester said. “Some of the things that I had to do were really disturbing for me. Particularly a scene involving a kitten, so it was an intense experience.”

Meester acts alongside “Friday Night Lights” star Minka Kelley. Even though Meester’s character in the movie torments Kelley relentlessly, in reality, the two get along just perfectly.

“I love Minka and I was so lucky to be able to work with her,” Meester said. “She has a light around her. She’s beautiful, incredibly talented, giving, and kind. She was really supportive throughout the whole thing.”

With the film being based and shot in Los Angeles, Meester never had to venture out of her comfort zone in terms of location. However, when it comes to having a roommate in real life, Meester is a bit out of her comfort zone there.

“I actually love living alone,” Meester said. “I used to have roommates all the time. It’s a challenge to live with people. You’re kind of taking on their friends and their life into your home.”

Known for her role as the posh Blair Waldorf on the CW series “Gossip Girl,” Meester had to undergo a considerable amount of de-glamorization to play the part of Rebecca. Something that she is not used to on the “Gossip Girl” set.

“The two roles cold not have been more different,” Meester said. “The entire experience all together was different, but the character, she is from a different place. Rebecca has a history of having mental disorder.”

Even though Meester’s character may be less than sane, Meester pleased with the final result.

“I’m really proud how it turned out,” Meester said. “I think it’s so scary, sexy, exciting, and fun, it’s definitely a ride.”

“The Roommate” opens nation-wide Feb. 4.