In the suffocating heat of the Texas brush, disgraced academic Dr. Aris Thorne is digging for redemption. But beneath the ruins of the Mission Nuestra Señora del Espíritu Santo, he unearths a history that should have stayed buried.

The excavation reveals a crypt of skeletons, the "Silent Choir," all bearing the same gruesome mark: a perfect hole drilled into the frontal bone. As Aris attempts to decode the logic of these ancient surgeons, a low-frequency vibration begins to rise from the earth—a sound that isn't heard, but felt.

As the camp descends into madness and the feral "Night Runners" close in from the darkness , Aris realizes that the mission wasn't built to keep the wilderness out, but to keep something else in. When the pressure builds inside your own mind, how far would you go to let it out?

Arthur finds a rusted camera in his closet containing a roll of undeveloped film. Paralyzed by an irrational fear, he tries to destroy it, but his wife insists he develop the pictures to "move on." What emerges in the darkroom is a terrifying sequence of images that reveals the shocking truth about his past—and the reason he can never leave his house.