The Stepdaughter

Jesse Conner runs a ranch in California with his ailing wife Maggie, his daughter Linda, and his son Buddy, who goes to a special education school. When Will, one of their horse handlers, is murdered at a hotel in Los Angeles, Jesse hires Susan Heller to fill Will's position. Linda, who has a large collection of mystery novels, is immediately suspicious of Susan, so Linda decides to get Jesse's mechanic, Paris, to help her figure out whether or not Susan is up to something. (imdb)