To Jill Johnson (Camilla Belle), it was the perfect babysitting job. The parents were away, the fridge was stocked and the children were tucked into bed. But then the phone rang and an ominous voice asked, `Have you checked the children?' Now, locked in with the lights out and the curtains drawn, a panicky Jill phones the police, who trace the calls - only to inform her they`re coming from inside the house. And as the frightened teenager goes upstairs to check, Jill`s quiet night of babysitting is about to turn into a nerve-shattering nightmare of suspense, horror and dread.