An Italian-American family move into a house built on an ancient Indian burial ground as they think it's the house of their dreams.
However the family ends up getting into quarrels when they move in to the house as the wife of the family named Dolores Montelli (Rutanya Alda) tries to keep the family together with her christianity.
The oldest son named Sonny (Jack Magner) doesn't see eye to eye with his abusive father as he behaves obnoxious and is suddenly posessed by an evil spirit as the spirit traps him when he tries to escape from it.
He is fascinated with his sister Patricia (Diane Franklin) and then the next thing you know he seduces her.
Next, he does an evil deed when Montelli tries to bless the house as the evil spirit tells him to stay away from him.
Then after he celebrates his birthday late at night his face turns very demonic and is forced to murder his family with a shotgun.
Montelli feels responsible, and tries to save the possessed boy's soul.

There's an effective moment with the character Dolores Montalli when she feels a presence in the laundry room of the house which she seems to do not too bad but sometimes looked a little overly dramatic but there's a very good camera shot on it.
Then late at night there's more good camera shots of the evil spirit wandering the house too approaching Sonny Montelli but there's no reaction to him which looks normal as watching the film here is kept a surprise since this is just the beginning of the story as well there's other spooky moments like a door banging and no one is there and paintbrushes moving by themselves drawing grizzly art with windows opening and shutting.
There's a real intense scene with the characters Anthony and Dolores acting temperamental and violent then we have a great moment with Sonny pointing a shotgun towards Anthony looking menacing.
The story definetely looks disturbing when Sonny slowly turns evil and he searches some parts of the house like the cellar where he sees illusions of a hand showing good shocking expressions when the evil spirits follows him as he tries to run away from it and poltergeists starts invading the whole house afterwards.
There's a good creepy scene between Patricia and Sonny as brother and sister as he tries to seduce her in which the scenario looked very soft and calm like.
There's a wonderful intense scene with Father Adamsky when he spots an illusion of blood in the parents bedroom while trying to bless the house. Along with a good evil laughter by Sonny by using his possessive powers to make things look twisted.
There is a touching scene when Sonny celebrates his birthday with his family looking like they'll be happy after all but of course the terror starts later on which disturbs this happy moment later on.
Then the terror begins when Magner takes the shotgun and goes on a killing spree which looked great and we have a perfect scared reaction by Patricia. P_lus Sonny's face looked totally demonic changing all of a sudden which looked terrifying while watching the movie.
There's lots more including an exorcism in the Amityville house as that was well performed here.
Bottom line is that t his one was the prequel to the first one but is totally fictional as it was based on the real life family of the DeFeo's but when you watch this flick you can tell that the whole story is extremely fabricated. It seems like a total ripoff on The Exorcist and The Omen put together. It's not overly terrible thank god but not that good either. It still had it's admirers though as some adore it but I wasn't one of them.

Burt Young (Anthony Montelli) is terrific with his role as an intimidating father with his aggression making it look like those real scrict Italian people that behaves violently when angered.
Jack Magner (Sonny Montelli) does very well too with the goin on's at the house and it's disturbing when he becomes slowly possessed too when he is so innocent from the beginning of the film. He definetely shows great evil expressions later on in the film
Diane Franklin (Patricia Montelli) also does a great job as the innocent but confused sister.
James Olson (Father Adamsky) plays a good and calm preacher.
However, Rutanya Alda (Dolores Montelli) is a little over the top and seems a little silly with her performance as she is meant to be truly intense and serious.

There's a brief breast shot of Diane Franklin when she is about to be seduced by the actor who plays her brother.

A woman is shot bloodily in the stomach.
A posessed boys face is peeling off.

The music was composed by Lalo Schifrin who did the same for the first film and shows some of the same elements from the first film along with sharp and creepy violin playing.