Run (The Hunted 1)

Sixteen-year-old Reid thinks life is back to normal. His sister Lucy
pulls herself together and cuts him free from a year of foster care. She
promises to take care of him, that her new boss and her new life are
what they both needed to start again. Until Reid is taken in the middle
of the night, dumped in a wild stretch of forest far from home with no
idea why he is there. Lost and afraid, he learns to run from the hunters
who prowl the darkness, their only pleasure chasing down kids like him.
And killing them.