This horror/suspense story set in a small American town surrounded by a dense forest. The town is haunted by a creature that has a tradition of taking young boys from their families when they turn thirteen. The story follows the journey of a teenage boy named Alex, whose younger brother is taken by the creature.

Alex embarks on a quest to rescue his brother and uncover the truth behind the creature's existence. Along the way, he discovers ancient symbols in the forest and encounters the creature, which reveals its true nature to him. Alex also learns of a dark secret in his town's history involving a father who was willing to sacrifice his own son to appease the creature.

As Alex delves deeper into the mystery, he faces danger at every turn, but he persists in his search, driven by his love for his brother. Eventually, he confronts the creature and discovers that the only way to save his brother is to offer himself up as the thirteenth offering.