Kim Jee-woon's psychological horror-show begins as two cute siblings, Soo-Mi and Soo-Yeon, return home after getting treated in a hospital. Right away, the elder sister assumes her stepmother is abusing her younger sibling.
The truth, however, has more to do with mental instability, which is conveyed through creeping dread, cameos from ghost kids, and a familiar plot twist that's handled quite well.
In 2009, American audiences ignored the stateside remake, The Uninvited, though it's not as bad as one would think. Compared to Jee-woon's terrifying original, though, it's a Disney Channel special.