Emelie

On the eve of their thirteenth wedding anniversary, Dan and Joyce head into the city to celebrate, leaving their three children -- adorable Christopher, curious middle-child Sally, and big brother Jacob -- at home. However, when Maggie, their usual babysitter has to cancel, the Thompsons call upon a new girl, Anna (Sarah Bolger)... As the night creeps along, the kids slowly realize that Anna is not exactly who she claims to be.