Rod Serling
He does a fine job narrating these three segments, as if he were presenting them on The Twilight Zone, which obviously this film took inspiration from. Possibly Night Gallery as well, which he also hosted at that same time(1973). All that's missing are the paintings!
Spooky and atmospheric film, if a bit amateurish at times, though has a distinct aura of melancholy about it.
http://en.wikipedia.org/wiki/Encounter_with_the_Unknown