The Darkness

Peter and Bronny Taylor go on a vacation to the Grand Canyon in Arizona with Stephanie, their teenage daughter, and Mikey, their adolescent autistic son. Mikey discovers a small Kiva cavern, where he finds black rocks with symbols on them. He takes the rocks, keeping a secret untold.

When the Taylors return home, strange things begin to happen. Bronny finds that the kitchen taps keep turning on, and Stephanie sees handprints on a steamy mirror, both of which Mikey blames on “Jenny”. After Stephanie gets home from school, she vomits into a container and puts it under her bed. Bronny catches her, and she and Peter learn that Stephanie has been throwing up for a while; there are many such containers under her bed. They take Stephanie to a hospital for help, leaving Mikey at Bronny's mother's house. Bronny's mother finds Mikey trying to kill her cat, much to Peter’s disbelief.