This review is from: The Texas Chainsaw Massacre - Original Uncut Edition  [DVD] (DVD)As far as I can tell this is the 1974 original film and not the remake so the previous reviewers may be mistaken. Certainly the picture displayed by Amazon is the 1974 original.
If so (and I haven't seen the remake) this is one of the most important horror films made. What is most surprising is that this film leaves so much to the imagination. You never really see anything. You certainly hear the chainsaw but the results are left for you to imagine, which is far more effective. What you do see is quite disturbing. Leatherface is a hideous nightmare in a human face mask. His first appearance is truly shocking, and there are number of scenes which feature him that have become iconic. Especially the last scene in the film, which is marvellously shot. Even more surprising is that in the last 20 minutes of the film, in amongst all the terror, an element of black comedy creeps into the film.
It may not be the best ever horror film, but its viseral power is not to be underestimated 33 years later. You have been warned....