Voices (2007) aka Du saramida (Someone Behind You)

After witnessing a family member thrown of a balcony by her fiance on her wedding day and the violent stabbing of her aunt, a young woman comes to realize she may be next in line. She desperately tries to find out why those around her turn on her and why she seems marked for death. Who can she trust - where can she turn for help when it seems everyone is out to get her. If only she can survive the murderous rage of friends and even her own family long enough to uncover the secret.

This creepy, supernatural thriller revolves around the paranoid belief that those dearest to you may want you dead.

Original title: 두 사람이다 (Du saramida; Someone Behind You)

Stars:
Yoon Jin-seo, Park Ki-woong, Lee Ki-woo, Kang Yi-seok, Kim So-eun, Lee Kan-hee, Jeong Yu-mi, Ahn Nae-sang, Oh Yeon-seo