"Don't trust old people." -Husband, as the end credits rolled.
(WARNING! This is a spoiler heavy review)
Rosemary and Guy are a young married couple who have decided to rent a great apartment in the Bramford apartment building in New York City. The Bramford has a somewhat morbid history - it was apparently home to a couple of cannibalistic serial killers, and also someone named Adrian Marcato, who supposedly conjured up what he called "The Living Devil" in the late 1890's.
Guy is an actor who has done theater and some commercial work. Rosemary is longing for children and spends a lot of time redecorating the apartment. Soon the two meet their elderly neighbors, Roman and Minnie Castavet who are kind of nosy but seem like nice people. Things don't seem to be going that great for Roe and Guy, he loses a part in a big production to an actor names Donald Baumgart. Guy also seems to really be digging all the time spent with the Castevets, making them almost surrogate parents which doesn't sit too well with Rosemary. He gets a break when poor Donald Baumgart is inexplicably stricken blind and Guy steps in to take his part. He also tells Rosemary that they can finally start to try to have a baby. He has even figured out when on the calendar is the best time for them to make a baby. What a guy!
On "baby night" Minnie drops by some chocolate mousse - or mouse, as she calls it - for them to have for dessert. Rosemary doesn't like the taste and puts most of it in her napkin. She's had enough however to incapacitate her and she goes into a bizarre dream sequence involving a lot of her neighbors - who are all naked and old, eeewww - a visit to the Sistine Chapel and a lovely boat cruise. This ends with her getting raped by the devil.
She wakes up the next morning with a wicked hangover and scratches all over her body. Loving husband Guy says, "Don't worry, I've already filed my nails down. I didn't want to miss baby night." NICE.
So Roe ends up pregnant and pushed into getting the "best Doctor in New York" who just happens to be a good friend of the Castavets. Dr. Sapirstein prescribes special herbal drinks made by Minnie. Pretty soon Rosemary starts to look terrible. Her friend Hutch comes by to see her and can't believe how awful she looks. (This is one of those times where a young Mia Farrow is the perfect person for this role. She can looked pale and hollow-cheeked like no one else.) Hutch calls her late that night and says he must meet her the following morning. Poor Hutch - that next morning he falls into a coma, never to recover.
Roe is not having an easy pregnancy, she is in terrible pain all the time but Dr. Sapirstein keeps saying it will subside. Finally Rosemary breaks down to some of her girlfriends - at this point it has been several months that she has been hurting - and they insist she get a second opinion. She tells the ever supportive Guy and he pretty much forbids her to see another doctor. Right in the middle of this argument the pain suddenly stops. Next we see Rosemary she is the picture of a healthy pregnant woman.
We find out that Hutch has passed on and has left a book for Rosemary about witches. After reading the book Rosemary start to realize that there are some strange things going on and starts to freak out. She attempts to get help but to no avail.
SPOILER ALERT FOR ENTIRE ENDING!
All the old people show up at the apartment as Rosemary is going into labor. They sedate her and she wakes up to be told by Guy that the baby is a boy and it's fine. When next she wakes up Dr. Sapirstein and Guy are saying there were complications and the baby is dead. The old folks are watching Roe around the clock and she starts to smarten up and stop taking all the pills they keep giving her. One night she grabs a big ass knife and figures out a way into the Castavets apartment where she finds Guy and all the neighbors gathered.
Phew, that was long. I really thought this movie was going to be scarier than it was, at least a few good scares. Nothing of the sort. Not even any real suspense. Mia Farrow was great playing the "Deer in the Headlight" scared young woman - she is so young. John Cassevetes is the perfect jerk who thinks it would be a good idea for his career to let his wife get impregnated by the Devil. It was nominated for numerous awards, and Ruth Gordon who plays Minnie Castavets won an Oscar for Best Supporting Actress. Screenplay written and directed by Roman Polanski. Some moments of really good cinematography and lighting. All of which is why I rated it as highly as I did. I had thought of it as a "classic" and it may be one in the Drama category - but I don't really think it actually could be considered Horror. Kind of a bummer.