The first half hour is ever babysitters nightmare, and a classic, terrifying scene in film history. After that, the film loses focus, as well as the female lead, and becomes a mediocre character study and a worse killer on the loose story. Still, the intro and climax offer excellent scares and original camera work. It is interesting to see the typically hilarious Carol Kane take up a serious role, making it one of her more memorable appearances, and Beckley is chilling at times and empathetic at others. Not the best example to come out of the peak Slasher era, but a must see for most horror fans. A babysitter is receiving frightful phone calls, only to find out they are coming from inside the house!