Rosemary's Baby was Ira Levin's second published book. It sold over 4 million copies, making it the bestselling horror novel of the 1960s.

Ira Levin chose the name 'Bramford' in honor of horror writer Bram Stoker.

While touring the apartment for the first time, they notice that a large cabinet is moved in front of a door in the hallway. They move the cabinet and open the door, only to find a perfectly normal closet.

Their friend Hutch informs them of the Bramford building's history of cannibalism and murder.

Rosemary quickly becomes friends with her elderly neighbors, Roman and Minnie Castevet, who are a bit eccentric and nosy but seem harmless enough.

When Rosemary becomes pregnant, her new neighbors suggest she see an obstetrician, Dr. Sapirstein, who tells Rosemary that rather than taking the usual prenatal vitamins, Minnie will make her a special herbal drink to keep the baby healthy.

Apart from certain scenes that accentuate a ticking clock, sounds and colors are muted. The emphasis is on Rosemary's loneliness, fragility, isolation, and eventual paranoia.

Guy and Rosemary return home to find that Terry has apparently thrown herself to her death from the window of the Castevets' seventh-floor apartment.

Rosemary's acceptance of the necklace knowing that Terry had been wearing it at the moment of her death seems curiously naive.

The actor who was originally cast goes inexplicably blind.