The Texas Chainsaw Massacre (1974)
Promise me something: if you see someone's grave has been vandalized, don't investigate anything. Maybe buy a new tombstone or spruce up the grave site, but leave it at that. Unfortunately, The Texas Chainsaw Massacre characters Sally (Marilyn Burns) and Franklin (Paul A. Partain) aren't given that advice when they see their grandfather's grave has been depredated. After setting out to find out why, they come across group of murderers and must fend off the chainsaw-wielding Leatherface (Gunnar Hansen), who dons a mask made of human skin.