The film adaptation has supplanted the novel in pop culture, but the novel was a huge hit for Levin—and the film actually sticks to the plot and dialog so closely you really do get a feel for the novel from watching it. The story of a young woman who becomes pregnant after a nightmare gets its terror not from the well-known twist of the baby’s parentage (hint: not her husband), but from the increasing isolation Rosemary experiences as her suspicions about everyone around her grow. So many threads tie into the terror, from the emotional and economic uncertainty of a struggling young couple to the simple fear any mother has for their child, all expertly knotted into a story that will keep you awake at night.