At first glance, Phil Pendleton and his son Adam are just an ordinary father and son, no different from any other. What no one knows is that Phil is a prisoner, and that up until a few weeks ago and a chance encounter at a grocery store, he had never seen the child before in his life.

The blizzard begins pummeling the Midwest on Christmas Eve, leaving hundreds of passengers stranded at Chicago's O'Hare International Airport. Todd Curry doesn't need another reason to disappoint his son, so he joins three other people in renting the last four-wheel drive available and they set out into the blinding snow. Only two hours into the treacherous trip west, Todd swerves to avoid a man in the middle of the highway. The stranger claims his daughter is lost somewhere out in the snow.

This forest isn't charted on any map. Every car breaks down at its treeline. Mina's is no different. Left stranded, she is forced into the dark woodland only to find a woman shouting, urging Mina to run to a concrete bunker. As the door slams behind her, the building is besieged by screams. Mina finds herself in a room with a wall of glass, and an electric light that activates at nightfall, when the watchers come above ground. These creatures emerge to observe their captive humans and terrible things happen to anyone who doesn't reach the bunker in time.

The West Texas desert towns of Inferno and Bordertown have been slowly dying. The Snake River isn’t the only thing that divides them. Racism and gang wars have turned the sun-scorched flatlands into a powder keg. If anything can unite them now, it’s the UFO that comes crashing through the clouds. It brings with it a young alien named Daufin, a fugitive who has taken human form. She knows the terror that awaits this planet—because it’s looking for her.

When Laurie was a little girl, she was forbidden to enter the room at the top of the stairs. It was one of many rules imposed by her cold, distant father. Now, in a final act of desperation, her father has exorcised his demons. But when Laurie returns to claim the estate with her husband and 10-year-old daughter, it's as if the past refuses to die. She feels it lurking in the broken moldings, sees it staring from an empty picture frame, hears it laughing in the moldy greenhouse deep in the woods.