There's something knocking on the window. Eddie's parents may be arguing about the disappearance of his infant brother Danny, but Eddie's facing a terror all of his own. There's a strange figure outside that claims it has Danny safe and sound - all Eddie needs to do to get his brother back is open that window. Eddie's father is filled with guilt over his relationship with his own lost brother. His mother has been abandoned to navigate her grief and terror alone. His grandmother carries with her a disturbing and all-too-relevant truth about their shared family history. As minutes tick by and hope for Danny grows ever smaller, the very fabric of their world disintegrates, welcoming eldritch terrors of unspeakable provenance to their doorstep. The family is losing a decades-long struggle against an entity that is not of this world, and its hunger threatens to swallow them whole.