One of my friend is looking for a movie that he saw around 15 years ago on tv (it could be less or more than 15).
The plot is that: a part of a family (father, mother, brother), that lives in an american country house, is killed by someone. Only the sisters survive but they are kidnapped by the same killer.
One of the sisters (the protagonist) have to save the others.
At the end is discovered that the murderer is the protagonist.