When I was in High School I dated this girl, Carolyn. Her previous boyfriend Jamie, was involved in a pretty shitty story. He and I already knew of each other and had talked a few times. He had these two other friends who were kinda bad news. Also, there was this girl, Melanie Richey who went the the cross-town high school. She was super popular; everyone loved her. She was maybe a sophomore. She was a really good girl too, like always doing the right thing, polite and all that.
One night, Melanie decides to sneak out of her house and go to a party. Jamie and his two friends were at this party. One of the friends decided he was going to hook up with Melanie. He spent most of the night following her around to get her drunk. She was really resistant to it at first but eventually gave in to the peer pressure. he had been feeding her some kind of drugs too, either X or LDS, but that supposedly was fake. She ended up getting pretty sloshed and he gave her something else and they all left together. She and this dude were in the back seat when she passed out. The dude was not all with it and strongly concerned Melanie was dead. They had no idea what to do with her so they drive out in the woods.
Dude decides he's getting laid anyhow and has sex with her on the hood of the car. They still believe she's dead at this point and aren't about to visit the authorities. The second guy (not Jamie) has a brilliant idea. We'll drag her down into this ravine, put a pipe bomb in her mouth to destroy the dental records and just leave her out here in the middle of nowhere.
They do that.

 Her remains weren't found for about 45 days. The whole community put together this "Find Melanie" campaign with posters and tv adverts and candlelight vigils; the whole deal. People worried about her for a long time. Much later, Jamie got arrested on an unrelated drug charge and mentioned something about the story to the police. Eventually they found her remains.

Autopsy later reveals she was alive the whole time and in some kind of aware-but-not-able-to-do-anything state. She died -raped, drugged, half dressed, in a pile of leaves- when her face exploded.
They were eventually caught and sentenced to jail. The two guys got pretty hefty sentences. Jamie, somewhere around 25 years.