The story of ‘Texas Chainsaw Massacre’ as an experience for its characters seems to be worse than their worst nightmares. This movie invokes disgusting terror of most horrifying nightmare. It's a film based on real events. It is one of the best horror movies ever made because it scares you without having too lurid content. Like Roman Polanski's The Tenant and Rosemary's Baby, this movie gradually builds up the tension.
The movie has great cinematography, elements of a great mystery movie and it affects you by highlighting the most psychotic and sadistic parts of psyche. The last victim of the Chainsaw-killer (Sally) runs for her life and she begs to the owner of the barbeque for her life, who turns out to be a sadist Chainsaw-gang-member. To aggravate the tension in the climax, the psychotic sado-masochist man who had met Sally's group earlier in the day, joins the gang and to even more horrifying end the grandpa starts sucking blood out of Sally's finger like a devilish infant. This movie is a horror masterpiece and seems to be the platform on which movies like Wrong Turn have been made; but unlike Wrong Turn (where devils are mutants and not normal humans), the sado-masochistic killers in this movie seem much close to human's dark psyche and in a way it's similar to The Shining.
Performances are perfect and so is the direction. There seem to be no flaws in the flow of the story and movie is short enough to sustain the stress it creates till the end.