Manderley is gone. Since the fire had destroyed their home, Mr. and Mrs. de Winter have lived in a secluded hotel away from England. Occasionally, Mrs. de Winter recalls the circumstances that had brought Manderley and Maxim de Winter into her life.
A shy, sensitive orphan, Mrs. de Winter had been traveling about the Continent as companion to an overbearing American social climber, Mrs. Van Hopper. At Monte Carlo, Mrs. Van Hopper forced herself upon Maxim de Winter, owner of Manderley, one of the most famous estates in England. Before approaching him, Mrs. Van Hopper informed her companion that Mr. de Winter had been recovering from the shock of the tragic death of his wife, Rebecca, a few months previously.
During the following days, the young woman and Mr. de Winter become well acquainted; when Mrs. Van Hopper decides to return to America, Maxim de Winter unexpectedly proposes to her companion. Already deeply in love with him, the young woman accepts, and they are married shortly afterward.
After a long honeymoon in Italy and southern France, Mr. and Mrs. de Winter return to Manderley. Mrs. de Winter is extremely nervous, fearing that she will not fit into the life of a great estate like Manderley. The entire staff gathers to meet the new mistress. Mrs. Danvers, the housekeeper, who had been devoted to her former mistress, immediately begins to show her resentment toward the new Mrs. de Winter.
Gradually, Mrs. de Winter pieces together the story of Rebecca. She learns that Rebecca had been a beautiful, vivacious woman and a charming host. As Mrs. de Winter becomes acquainted with the relatives and friends of her husband, she becomes convinced that they find her lacking in those qualities that had made Rebecca so attractive and gracious. One day, she goes secretly to the closed rooms Rebecca had occupied. Everything is as Rebecca had left it before her fatal sail in her boat. Mrs. Danvers suddenly appears and forces her to view Rebecca’s lovely clothes and other personal possessions.
When the bishop’s wife suggests that the traditional Manderley dress ball be revived, Mr. de Winter gives his consent. Mrs. de Winter announces her intention of surprising them all with her costume. At Mrs. Danvers’s suggestion, she plans to dress as an ancestor whose portrait hangs in the hall at Manderley; but as Mrs. de Winter descends the stairs that night, a silence falls over the guests, and her husband turns angrily away without speaking. Realizing that something is wrong, Mrs. de Winter returns to her room. Beatrice, Mr. de Winter’s sister, goes to her immediately and explains that Rebecca had worn the identical costume to her last fancy dress ball. Again, Mrs. Danvers has humiliated her new mistress. Although Mrs. de Winter reappears at the ball in a simple dress, her husband does not speak to her all evening. Her belief that he has never ceased to love Rebecca becomes firmly established in her mind.
The next day, a steamer runs aground in the bay near Manderley. A diver is sent down to inspect the damaged steamer and discovers Rebecca’s boat and in its cabin the remains of a human body. Mr. de Winter had previously identified the body of a woman found in the river as that of Rebecca.
Unable to keep silent any longer, Mr. de Winter tells his wife the whole story of Rebecca and her death. The world had believed their marriage a happy one, but Rebecca was an immoral woman, incapable of love. To avoid the scandal of a divorce, they make a bargain: Rebecca is to be outwardly the fitting mistress of Manderley, but she would be allowed to go to London periodically to visit her dissolute friends. All goes well until she begins to be careless, inviting her friends to Manderley and receiving them in the boathouse. Then she begins to plague Frank Crawley, the estate manager of Manderley, and Giles, Mr. de Winter’s brother-in-law. After Frank and others had seen Rebecca’s cousin, Jack Favell, at the boathouse with her, gossip ensued. One evening, Mr. de Winter follows her to the boathouse to tell her that their marriage is at an end. Rebecca taunts him; she suggests how difficult it would be to prove his case against her, and asserts that should she have a child it would bear his name and inherit Manderley. She assures him with a smile that she would be the perfect mother as she had been the perfect wife. She is still smiling when he shoots her. Then he puts her in the boat and sails out on the river. There he opens the seacocks, drills holes with a pike, and, leaving the boat to sink, rows back in the dinghy.
Mrs. de Winter is horrified, but at the same time, she feels a happiness she had not known before. Her husband loves her; he had never loved Rebecca. With that discovery, her personality changes. She assures her husband that she will guard his secret. A coroner’s inquest is held, for the body in the boat is that of Rebecca. At the inquest, it is established that a storm could not have sunk the boat; evidence of a bolted door, the holes, and the open seacocks point to the verdict of suicide, determined by the coroner’s jury.
Later that night, after the jury’s verdict, a drunk Jack Favell appears at Manderley. Wildly expressing his love for Rebecca and revealing their intimate life, he tries to blackmail Mr. de Winter by threatening to prove that de Winter killed his wife. Mr. de Winter calls the magistrate, Colonel Julyan, to hear his case. Favell’s theory is that Rebecca had asked her husband to free her so that she could marry Jack, and that de Winter, infuriated, had killed her.
From Rebecca’s engagement book, it is learned that she had visited a Dr. Baker in London on the last day of her life. Colonel Julyan and Mr. and Mrs. de Winter, with Favell following in his car, drive to London to see Baker. On checking his records, the doctor finds that he had examined a Mrs. Danvers on the day in question. They realize that Rebecca had assumed the housekeeper’s name. Baker explains that he had diagnosed Rebecca’s ailment as cancer in an advanced stage. Colonel Julyan suggests that the matter be closed since the motive for suicide had been established.
Driving back to Manderley after leaving Colonel Julyan at his sister’s home, Mr. de Winter tells his wife that he believes that Colonel Julyan had guessed the truth. He also realizes that Rebecca had intimated that she was pregnant because she had been sure that her husband would kill her; her last evil deed would be to ruin him and Manderley. Mr. de Winter telephones Frank from the inn where they had stopped for dinner, and the estate manager reports that Mrs. Danvers has disappeared. His news seems to upset Mr. de Winter. At two o’clock in the morning, they approach Manderley. Mrs. de Winter has been sleeping. Awaking, she thinks by the blaze of light that it is dawn. A moment later, she realizes that she is looking at Manderley, going up in flames.