Murder Elite (1985)

After spending all of her inheritance, scheming Diane returns from The United States to her family's estate in the English countryside, where her sister Margaret takes care of the family's stables with the help of two farmhands, Ron and Jimmy. Diane is interested in Ron but Margaret has had enough of her sister's irresponsible behavior and promiscuity, especially after Diane admits to her that she had had several tremulous failed relationships in the States and even had to have an abortion. They fight over the future of their estate as well as the direction of their lives. However, this family drama is interrupted when the police shows up to question them about the brutal murder of a local girl in the nearby forest. None of the four have alibis but they also lack motivation to commit the murder, so they are left alone for the time being. Suspicion begins to grow in the household as the killings continue.