Curious to inspect into the secrets of Manderley, Mrs. de Winter climbs the stairs and enters into the doors of the West Wing that lead to Rebecca's dark bedroom. She immediately opens the drapes and a window. Mrs. Danvers appears and fully opens the "lovely" room to light: "Everything is kept just as Mrs. de Winter liked it. Nothing has been altered since that last night." The housekeeper reminisces about the former "ghostly" but beloved mistress of the house - with highly muted suggestions of a possible lesbian relationship.

In one of the film's most chilling scenes, she proudly shows off Rebecca's dressing room possessions ("This is where I keep all her clothes") - including her furs and lingerie. Mrs. Danvers gloats that Rebecca "knew everyone that mattered. Everyone loved her."

Mrs. de Winter is urged to sit at Rebecca's dressing table and follow the routine of her precise habits. Mrs. Danvers pretends to brush her hair and repeats conversations between Rebecca and herself. She also shows off an embroidered pillowcase on the bed (monogrammed with an "R") and its "delicate" sexy nightgown inside - one of Rebecca's most intimate articles of clothing: "Did you ever see anything so delicate. Look, you can see my hand through it." Mrs. Danvers, in league with the world of spirits, suggests to a shaky, fragile, and crying Mrs. de Winter that Rebecca still inhabits the house and comes back from the dead to watch the living - the new couple ("I wonder if she doesn't come back here to Manderley and watch you and Mr. de Winter together"). Prodded by the psychological ramblings of Mrs. Danvers, Mrs. de Winter begins to be persuaded that she is being haunted by the woman:

Mrs. Danvers: You wouldn't think she'd been gone so long, would you? Sometimes, when I walk along the corridor, I fancy I hear her just behind me, like a quick light step. I couldn't mistake it anywhere, not only in this room, but in all the rooms in the house. I can almost hear it now. Do you think the dead come back and watch the living?
Mrs. de Winter: I don't believe it.
Mrs. Danvers: Sometimes, I wonder if she doesn't come back here to Manderley, to watch you and Mr. de Winter together. You look tired. Why don't you stay here and rest, and listen to the sea? It's so soothing. Listen to it. Listen.

She also encourages her mistress to "listen to the sea" - crashing waves against rocks are superimposed over Mrs. Danvers standing at the window, and over an "R" monogrammed address book. Left alone in Rebecca's room for the day, the new Mrs. de Winter searches through stacks of ribbon-tied love letters - and finds an "costume ball" invitation to Jack Favell - with his handwritten note in reply that suggests that the first Mrs. de Winter and Favell had been lovers (he pens: "Rebecca - I'll be there - and how!").

Gathering up all her courage and fortitude, Mrs. de Winter summons Mrs. Danvers and demands that all of Rebecca's monogrammed stationary and personal effects be destroyed immediately: "I want you to get rid of all these things." When Mrs. Danvers protests, she stands up to Mrs. Danvers and asserts her controlling authority as mistress of the house:

I am Mrs. de Winter now.

Mrs. Danvers accepts the command: "Very well, I'll give the instructions." Hearing the arrival of her husband from his Londay day trip, Mrs. de Winter also asserts: "Mrs. Danvers, I intend to say nothing to Mr. de Winter about Mr. Favell's visit. In fact, I prefer to forget everything that happened this afternoon."

When her husband appears in the hallway, she joyfully rushes into his arms, and then asks permission to host her own fancy-dress costume ball to lighten up the atmosphere:

We ought to do something to make people feel that Manderley is just the same as it always was...Oh yes, but I want to, oh please! I've never been to a large party, but I could learn what to do, and I promise you, you wouldn't be ashamed of me...I'll design a costume all by myself and give you the surprise of your life.

While sketching various costume ideas for the ball, Mrs. Danvers suggests that the second Mrs. de Winter find inspiration from the large family portrait in the hall at the top of the stairs, a portrait of Lady Caroline de Winter (one of Maxim's ancestors), dressed in a white ruffled dress: "I heard Mr. de Winter say that this is his favorite of all the paintings." Unknowingly, the heroine is planning to be dressed up exactly like Rebecca once was.

At the large costume ball at Manderley, Mrs. de Winter expectantly prepares to surprise her husband with her "secretive" costume - a copy of the white dress in the portrait. Innocent of Mrs. Danvers' evil designs, she glides down the great staircase to the ballroom, smiling, proud and radiantly dressed in an exact copy of the lavish white gown. She happily anticipates receiving her husband's approval and presents herself to her husband from behind: "Good evening, Mr. de Winter." When he turns to face her, he is not impressed - but appalled and angry at her for wearing the same kind of dress worn by Rebecca at the previous masquerade ball. He orders her to "take it off":

What the devil do you think you're doing?...Go and take it off. It doesn't matter what you put on. Anything will do. What are you standing there for? Didn't you hear what I said?

Her happiness in being exactly like Rebecca instantly turns to horror and despair. Thoroughly embarrassed and humiliated, Mrs. de Winter turns and rushes upstairs. She realizes that she has been set up by the manipulatively evil housekeeper. After catching a glimpse of Mrs. Danvers entering Rebecca's bedroom, she follows after her to question her advice, but instead is taunted and told that she will NEVER take Mrs. de Winter's place:

Mrs. Danvers: I watched you go down just as I watched her a year ago. Even in the same dress you couldn't compare.
Mrs. de Winter: You knew it. You knew that she wore it. And yet you deliberately stressed that I wear it. Why do you hate me? What have I done to you that you should ever hate me so?
Mrs. Danvers: You tried to take her place. You let him marry you. I've seen his face, his eyes. They're the same as those first weeks after she died. I used to listen to him, walking up and down, up and down, all night long, night after night, thinking of her. Suffering torture because he lost her.
Mrs. de Winter: I don't want to know. I don't want to know.
Mrs. Danvers: You thought you could be Mrs. de Winter. Live in her house. Walk in her steps. Take the things that were hers. But she's too strong for you. You can't fight her. No one ever got the better of her. Never. Never. She was beaten in the end, but it wasn't a man. It wasn't a woman. It was the sea.
Mrs. de Winter (weeping): Oh, stop it! Stop it! Oh, stop it!

Collapsing in tears on the bed, Mrs. de Winter fears that she can never equal Rebecca in her husband's affections, and that she is gradually losing her sanity. The demonic Mrs. Danvers opens the bedroom window for fresh air for the overwrought young woman, and then plays upon the fears of the over-identifying Mrs. de Winter. Vexed by the pervasiveness of the images and recollections of the dead Mrs. de Winter, the young wife comes close to committing suicide.

In this, the film's most horrifying scene, Mrs. Danvers plots to eliminate her by urging her to jump to her death from an open window because she can never be the true replacement and mistress of the estate: [The camera tracks back from outside the window, luring her to her doom.]

Why don't you go? Why don't you leave Manderley? He doesn't need you. He's got his memories. He doesn't love you - he wants to be alone again with her. You've nothing to stay for. You've nothing to live for really, have you? Look down there. It's easy, isn't it? Why don't you? Why don't you? Go on. Go on. Don't be afraid!

In a trance-like state and ready to end her life, distractions from explosive flares and shouts of the discovery of a sunken boat ("Shipwreck! Ship on the rocks") following a storm at sea prevent her from losing her sanity and jumping. From the window, she sees her husband leaving the house. Later that night, Mrs. de Winter searches for Maxim on the beach and runs into Ben - he hauntingly tells her: "She won't come back, will she? You said so."

On the misty beach, Frank tells her what has been discovered - the sailboat in which Rebecca had presumably drowned. She fears the terrible news will be "so hard" for "poor" Maxim - it will revive old memories and widen the breach between them: "It's going to bring it all back again, and worse than before." Mrs. de Winter finds Maxim sitting alone in the beach house - he is morbidly depressed, but at least he has forgotten the costume incident from earlier.

Mrs. de Winter: Maxim, can't we start all over again? I don't ask that you should love me. I won't ask impossible things. I'll be your friend, your companion, I'll be happy with that.
Maxim: (He rises and embraces her.) You love me very much, don't you? (He kisses her gently.) But it's too late, my darling. We've lost our little chance at happiness.
Mrs. de Winter: No, Maxim, no.
Maxim: Yes. It's all over now. The thing has happened, the thing I've dreaded, day after day, night after night.
Mrs. de Winter: Maxim, what are you trying to tell me?
Maxim: Rebecca has won. Her shadow has been between us all the time, keeping us from one another. She knew that this would happen.
Mrs. de Winter: What are you saying?

In the high point of the film, he speaks to her for the first time about Rebecca and how she died. Now that a diver has found Rebecca's sail boat disgorged by the ocean after a storm, her body has also been discovered on the floor inside the boat's cabin. He is shaken, knowing that the wrecked boat will hold the body of his wife - because he put her there. In consternation, Maxim admits that he knowingly lied and identified the woman's body that washed up at Edgecoombe as Rebecca's even though he knew it wasn't her body. The woman, now buried in the family crypt and identified as Rebecca is not Rebecca, but some unknown, unclaimed stranger, belonging nowhere:

Maxim: I identified it, but I knew it wasn't Rebecca. It was all a lie. I knew where Rebecca's body was! Lying on that cabin floor at the bottom of the sea.
Mrs. de Winter: How did you know, Max?
Maxim: Because I put it there. Will you look into my eyes, and tell me that you love me now?

The revelation startles Mrs. de Winter. She stands, turns, and walks away:

Maxim: You see, I was right, it's too late.
Mrs. de Winter: No, it's not too late. You're not to say that. I love you more than anything in the world. Oh, please Maxim, kiss me please.
Maxim: No, it's no use. It's too late.
Mrs. de Winter: We can't lose each other now. We must be together always, no secrets, no shadows.

Although he had vainly tried to explain things (about Rebecca) to her earlier, she never seemed "close enough." She tells how difficult it was for her, because she was always being compared with Rebecca. She always doubted his love - and believed that he still loved Rebecca. His confession is surprising - he reveals that he "hated" her after their marriage:

Mrs. de Winter: How could we be close when I knew you were always thinking of Rebecca? How could I even ask you to love me when I knew you loved Rebecca still?
Maxim: What are you talking about? What do you mean?
Mrs. de Winter: Whenever you touched me, I knew you were comparing me with Rebecca. Whenever you looked at me or spoke to me, walked with me in the garden, I knew you were thinking, 'This I did with Rebecca. And this and this.' It's true, isn't it?
Maxim: You thought I loved Rebecca? You thought that? I hated her! Oh, I was carried away by her - enchanted by her, as everyone was. And when I was married, I was told that I was the luckiest man in the world. She was so lovely - so accomplished - so amusing. 'She's got the three things that really matter in a wife,' everyone said: 'breeding, brains, and beauty.' And I believed them - completely. But I never had a moment's happiness with her. She was incapable of love, or tenderness, or decency.
Mrs. de Winter (ecstatically relieved): You didn't love her? You didn't love her?