Rebecca Evans is the main antagonist of The Roommate.
She is portrayed by Leighton Meester.
She ends up being the roommate of Sara Matthews. The two quickly become close friends. However, Rebecca starts to become more obsessed with Sara. This starts with her threatening to kill Tracy (close friend of Sara) unless she stays away from Sara. Tracey moved to another dorm in fear of Rebecca.
Later, another close friend of Sarah named Irene invited Sarah to move in with her. To ensure that Sara wouldn't accept the offer, Rebecca kills her pet cat, Cuddles, by putting it in a dryer. She then told Sara the cat ran away. To avoid being found out, Rebecca inflicted herself with injuries. She then told Sara that she looked for the cat but was assaulted by a thug. This caused Sara to feel bad and she decided to spend Thanksgiving with Rebecca.
Later, Rebecca hears from Sara that her designs professor, Roberts had kissed her, Rebecca decides to get rid of the professor by seducing him while recording their dialogue on a tape recorder to make it sound like he was trying to rape her.
Sara overheard a conversation between Rebecca and her father, learning Rebecca had trouble making friends. Rebecca's mother mentions that she is supposed to be taking medication. She also meets a former friend of Rebecca who resembles her (Sarah). Sarah and her boyfriend Stephen then found Zyprexa pills which are used to treat mental illness. Because of this, Sarah realized that Rebecca was crazy and she decided to move in with Irene.
Irene then went to a club where she saw Rebecca. The two of them kiss and head back to Irene's place. Sara then heads to Irene's house the next day but discovers her to be missing. Meanwhile, Rebecca impersonates Sara and kills her ex-boyfriend, Jason.
Sara then receives a text from Irene saying she needs her and discovers her being held hostage by Rebecca. Rebecca then reveals that she was responsible for Tracy, Professor Roberts, and the deaths of Sarah's cat and ex-boyfriend so she could win Sarah's friendship. Rebecca then decides to kill Irene to get her out of the way but Sarah's boyfriend, Stephen shows up to stop Rebecca. Sara then decides to kill Rebecca by using the gun but the cartridge is empty.
Rebecca then gets angry and attempted to kill Sara by choking her to death. However, Sara then manages to stab Rebecca in the back with box cutters which kills her. Right before she stabs her, she whispers, "You were never my friend."