This is an older movie 60's or 70's. A woman and a man got to visit a home on the coast where the woman grew up. There is a man that there that is in love with the wife and chases her into the attic. The wife sees a woman chained up like an animal and realizes that that woman is her twin. There is a fire that kills the twin and the grandmother.

Blood Island (http://www.imdb.com/title/tt0062266/) aka The Shuttered Room.

The shuttered room?

Thans so much! That is the movie!!

THanks again both of you!

Is that a link to a film called the shuttered room? Or is it called blood island?

The movie is known by both names.