The Possession of Joel Delaney (1972)

Manhattan socialite begins to fear for her troubled younger brother when he starts behaving bizarrely and he seems to have been friends with a backstreet murderer.

The Possession of Joel Delaney is a dark horror film with much going for it. For one, it's among the earliest horror films to deal with the theme of spiritual possession. Also, it's one of those horror gems that doesn't need to resort to special effects or overt gore and violence to be effectively unsettling. It's a thoroughly well-written film as it blends eerie supernatural horror with a strong social commentary. The plot is compelling and quite off-beat as it builds to some chilling peaks and a finale that's splendidly suspenseful. It's a truly disturbing tale.