Scream Queen

the long version

A woman driving alone through the desert picks up a younger woman whose car has broken down on the side of the road. Later at the younger woman's job, the two ladies chat, revealing bits and pieces of their lives. After this meeting, the older woman leaves for an appointment with a man. She arrives at his apartment, where he's having sex with a woman. The woman confronts him. Turns out she's the living dead, come to bring the man to the other side.