A teenaged girl, frantic, runs out from her suburban house, looking behind her. She goes back in at the urging of her father, only run out again and take off in the car. Then, on the shore of a nearby lake she calls her parents and tells them how much she loves them. The movie then cuts to the next morning and we see she's dead--and horribly mangled.
The story goes to another teen girl, who goes out on a date with a guy to a movie theater. He's freaking out when he sees something so they take off to a secluded are of the woods and have sex in his car. Immediately afterwards he knocks her out. She awakens, died to a wheelchair in an old abandoned building. He explains that he's not going to hurt her but that she has to understand what's happening to her. You see, he's passed on a curse when he had sex with her. And with this curse and entity will come after you and kill you if it touches you. In order to avoid this you have to pass the curse onto someone else. She's convinced when she sees the naked woman coming after her--and then, on her college campus when the creature, in the guise of an old lady, pursues her. So now she has to make a decision-- run or have sex with someone to pass along the curse. She confides in her friends--and that definitely complicates things.
I was surprised at how effective this movie is, particularly the scenes when she's pursued by this creature. It's sort of like a zombie movie, sort of like a Japanese ghost story movie. And highly recommended because it's so different than the usual stuff that's out there.