After a personal tragedy leaves Rosemary and Guy Woodhouse anxious for a fresh start, the young married couple departs for Paris where Guy has landed a job teaching at The Sorbonne. Upon arrival a series of unfortunate events occur, and soon Rosemary and Guy are presented with an offer they can't refuse - an apartment with the most prestigious address in the city. They find comfort in this strange city among their new friends and neighbors, Roman and Margaux Castevet, but soon find the apartment comes with a haunted past. This well-to-do successful older couple take the newcomers under their wings and become very involved with the Woodhouse's lives. Meanwhile Rosemary spends some quality time with her dear friend Julie learning how to cook at Le Cordon Bleu. Everything seems wonderful as the couple decide to try to conceive a baby.

In this 2-hour conclusion Rosemary's health rapidly declines with her pregnancy while Guy's career takes off with the successful completion of his book. At the same time Roman and Margaux each take a peculiar and very intimate interest in the young couple. Untimely and gruesome deaths seem prevalent and we soon learn why. As Rosemary's due date approaches the truth about her baby becomes clear and everyone's true colors come to light.