3. Rosemary's Baby
Rosemary's Baby is a classic horror film for all occasions. Written and directed by Roman Polanski, it has a strong reputation within the demon-child horror sub-genre as one of the creepiest and most successful tales. Rosemary finds herself living next door to a couple of satanists who use witchcraft to summon a demon rapist that impregnates her. Rosemary is unaware of the demon spawn within her, but becomes suspicious throughout the film based on some rather unusual pregnancy symptoms. Sadly for poor Rosemary, her doctor tries to convince her that she is delusional when she confides in him. Only her old friend Hutch discovers the truth, and leaves Rosemary a book of witchcraft wherein she discovers her horrifying fate. Rosemary's Baby is not a full-on drama and, apart from the demon rape, there is very little visible horror. It works psychologically, and gets into the head of the viewer with slow-burning and insidious creepiness. Its length (just over 2 hours) is justified by the effect it has on the viewer, and is definitely not one to watch alone in your flat late at night.