Delta Mason, 22, leaves home one steamy summer night in her North Carolina town for some ice cream and does not return. The frantic family (mother Caroleena, father Bruin, brother Leavell and identical twin Delia) searches for her, a search complicated by the appearance of a hurricane bearing her name. Hurricane Delta is so massive that the townspeople must evacuate. But the Masons believe they have a compelling reason to remain. Only the athiest Leavell seems to understand that they will all be killed. But does the rest of the family know something about God and the spirit that Leavell must re-learn? Will his lack of belief kill them all, or will it save them?