William and Victoria Smith are a wealthy couple living in suburban New York, who thought they had it all, a nice house, three handsome sons, maids and butlers at their every beck and call. When Bill and Victoria decide to adopt a child from a local orphanage, however, they both find it rather odd that the orphanage didn't have any records of who this little girl was, but they adopt the little girl anyway, and name her Carol Anne.Eventually Bill and Victoria find out about Carol Anne's past and that she wasn't born, so much as created by a group of mad scientists who wanted to use her as a guinea-pig for experiments. Then, when one of these scientists; Dr. Matthew Fredericks finds out that this "test subject", who was given the codename Rosemary, was adopted, he sees her as a threat, and tries to dispose of her once and for all. Dr. Fredericks then hatches a plot to kidnap Carol Anne and turn her back into a guinea-pig for more experiments.Can the Smiths save their adopted daughter in time, before i