The Lost But Not Forgotten

I give credit to the title to my wonderful Girlfriend. I didn't come up with the title she did.

6 teens befriend each other at about age 7-8. They form a bond unable to be broken by anything. As the years go by they start staying out past curfew. One day, 8 years after they became friends, they get caught. They manage to get away with only minor punishment. Only 3 of the 6 end up going missing the next day. The others heartbroken and hurting stay close and try to find out what happened to their dear friends. Sadly 2 years later they part ways and move to three parts of the village (kind of a city but more in the country, not many buildings and everything). 5 years after the disappearance of their friends the last 3 find themselves back where they grew up together and in more danger than they ever thought they would be in.