1970's Horror Halloween Celebration!

Tomorrow is the first day of October, which has my favorite holiday, Halloween, in it, so I'm doing something special.  I noticed that a lot of great and/or memorable horror films were made in the 1970's.  Therefore, I am reviewing only movies from this decade all month long!  Also, it won't be just horror because I like variety, and Halloween isn't just scary; it's fun! And I get candy.  Also, I realize I only have one month left to make our costumes so I need to get busy.

The scariest movie!