Your older brother was a real fuck-up. Drugs, petty theft, got a girl pregnant, the works. He finally went just a step too far and ended up dead one day, so your parents finally decided it was time to take you and your little sister out of the city. Your family ended up in a small town in the ass end of nowhere, chosen because the school was supposed to be pretty good.
Well, a little scandal with state exams being opened early and administered as “practice tests” put the lie to that, but your family couldn't afford to move again. The drug problem was about as bad as the city, too, only the harder stuff wasn't easy to find anymore – everyone was too poor for the area to be a good market, but there was plenty of weed grown in someone's unused field and people could still get high off cough medicine. And there were more than a few teenage pregnancies around, too.
Not that you were at much risk of getting caught up in that stuff. Most of the people were related in some way, mostly cousins and through marriage, but it boiled down to the simple fact that your family were outsiders. You knew the pot was around, but it's not like anyone told you about it. Nobody liked you enough for an opportunity to become a teenage parent. Parties? Right out. Hell, you and your sister were lucky to find a seat on the school bus most days. It got to the point where you insisted your parents help pay for a car in her name instead of yours so she didn't have to get stuck on the bus again once you graduated a year ahead of her.
In other words, and not to put too fine a point on it, growing up in small-town America sucked. And you were all too happy to get out. But you were still curious about what you missed out on, so when you caught wind of one last party being held after graduation, you decided to crash it.
The strange music was the first sign that something was wrong. Not something issuing from somebody's radio or boombox or any speakers at all, but a rhythmic drumming sound. You could see the faint glow of a bonfire in the distance as well. It was all on the other side of a hill, a small depression up against the edge of somebody's private property where the trees grew wild.