1970’s or early to mid 80’s thriller I think set in a basement with a man who suffocated his victims with plaster over their bodies slowly ending with covering their mouth and nose with plaster of some type? I remember as a small child watching a movie that still haunts me to this day. I want to rewatch it to understand what I could have possibly watched on TV as a child. I assume it was a movie and not a TV episode but I can’t be certain. My recollection was that it was long, like a movie.
Basically it was a thriller where the man would suffocate his victims by strapping them to a table and slowly covering up their whole body with some type of plaster-ish material and it would end in the death by suffocation by covering up the mouth and nose with this material.