Bae Soo-mi: Shall we kill them?
Bae Soo-yeon: Let's set them free.
Bae Soo-mi: She'll have a cow if we mess with her precious. I'd hate to see that.

A Tale of Two Sisters (2003)
Plot summary
Directed by: Jee-woon Kim, Kim Jee-Woon
Starring: Jung-ah Yum, Geun-Young Moon, Kap-su Kim, Soo-jung Lim, Su-jeong Lim
After spending some time in a mental hospital, Su-mi returns to her father's home with her younger sister Su-yeon. Her father is distant, and her seemingly disturbed stepmother, Eun-ju, torments Su-yeon whenever she gets a chance. Su-mi protects Su-yeon from Eun-ju's cruelty, and from what appears to be a ghost haunting the house.
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