The Hallowed Ones Hallowed Ones Series, Book 1.

Katie is on the verge of her Rumspringa, the time in Amish life when teenagers can get a taste of the real world. But the real world comes to her in this dystopian tale with a philosophical bent. Rumors of massive unrest on the "Outside" abound. Something murderous is out there. Amish elders make a rule: No one goes outside, and no outsiders come in. But when Katie finds a gravely injured young man, she can't leave him to die. She smuggles him...