Black Christmas (1974)

Years before he made Porky’s and A Christmas Story — two diametrically opposite films — director Bob Clark made this movie with elements of both. It’s a bleak, spooky early slasher film set in a Canadian sorority house stocked with top-notch actors, including Olivia Hussey and Margot Kidder.

It will change the way you look at plastic bags and make you grateful that phone calls are a lot easier to trace these days.