I saw The Texas Chainsaw Massacre in 1976 in a cinema in Shepherds Bush. You could pick up a badge "I survived The Texas Chainsaw Massacre" in the foyer, on the way home. It's the only horror/slasher film that I've seen but it was very cleverly made. There was actually very little gore and guts, but a lot of room for your imagination to fill in some quite horrendous details. Brilliant, if you like that stuff.
RIP