This is a first rate religious themed horror thriller about demonic possession that preceded "The Exorcist" and uses a very similar plot template. The screenplay by Matt Robinson and Irene Kamp (from a novel by Ramona Stewart) sees wealthy socialite Norah Benson (Shirley MacLaine) becoming increasingly concerned about the mental state of her brother Joel (Perry King). After he's committed to a mental institution for attacking a man Norah begins a search for an explanation for Joel's actions, first through doctors and psychiatrists, but becoming more desperate she turns to the voodoo and Santaria practitioners in Spanish Harlem. She begins to believe that Joel is possessed by the spirit of a Puerto Rican murderer and in fear of her own life and that of her children, Peter (David Elliott) and Carrie (Lisa Kohane), she flees to their out-of-town beach house - the insane Joel isn't far behind them, however.

Directed by Waris Hussein, who delivers a slow-burning film that builds gradually, carefully and incrementally to a fantastically disturbing finale, while delivering a number of shocks and standout scenes along the way. The beach house climax of the film is brutal and features a number of sequences (particularly those involving Peter) that simply would not be allowed today - these scenes are virtually transgressive in their nature and no filmmaker would even consider such treatment of a minor today. Hussein punctuates the film with a number of powerful moments: the "exorcism" attempted by a Puerto Rican spiritualist and his congregation is brilliantly conceived and full of gnawing tension; Norah's walk through the ghetto in her furs and finery make a powerful statement about the difference between the haves and have-nots without uttering a word of dialogue, while two separate scenes of decapitated heads are sneaked in on the audience with such subtlety and lack of fanfare as to be doubly shocking. Adding to the overall strangeness is the relationship between Norah and Joel. The opening scene of the film suggests they are lovers rather than brother and sister, with their on-going interactions, including a shower scene and a "discussion" about sex, suggesting a wholly inappropriate relationship - this theme of implied incest runs through the film so openly it is difficult to even consider it subtext. The actors are all fine in what they do - a long-haired Shirley MacLaine is well cast as a haughty socialite type with a fine line in fashionable furs. Perry King is a touch anodyne in the earlier parts of the film but comes into his own in the later part and is truly frightening at the beach house finale. Young David Elliott, however, deserves the most plaudits for the brave and gritty work he does as part of that gruelling and disturbing finale.

"The Possession of Joel Delaney" is a first class effort that touches on many themes of cultural and religious differences; class distinctions; broken family relationships (and incest). It is also, however, a great horror thriller that is full of splendid moments and plenty of tense, frightening situations. The ending, in particular, is powerfully shocking and brutal, helping make the overall film a bit of underrated little gem. ( )