The guests gather together around a champagne table on the Lord's estate porch before going to Uncle Willie's pre-wedding party. Mrs. Lord complains about the length of Dinah's party dress:

Mrs. Lord: I think that dress hikes up a little behind.
Dinah: (mischievously) No, it's me that does.

Tracy remains upset about her previous four conversations with Mike, Dexter, George, and her father, who criticized her as a haughty, unapproachable, unloveable "rich and mighty" snob without vulnerability or humanity (a "prig," "spinster," or "goddess(es) of any variety"). Uncle Willie, a typically randy, dirty old man is smitten by Miss Embrie: "You're a vision of loveliness." Mr. Lord confesses his real identity and the knowledge that the family knows why Mr. Connor and Miss Imbrie are there - they're interlopers from SPY Magazine. Tracy's kid sister is led away with a satirical grin on her face:

I can tell there's something in the air because I'm being taken away.

As the guests depart, Tracy - normally a non-drinker - quickly downs three champagne glasses, to hide her uncertainty about the impending romantic entanglements and to fortify herself for the evening and for her second marriage. [Her drinking frees her to look honestly at herself and help cure her of a too-exacting, perfectionistic "goddess" complex.] During her final sip of champagne, the scene dissolves to Uncle Willie's house where the late-night party is already in progress. Tracy dances on the outdoor terrace with her beau George. Under the magical illumination of the moonlight and still feeling the effects of alcohol, she tells him a story of a hopelessly-romantic Chinese poet. Stuffed-shirt George coldly remarks about the lateness of the hour, and doesn't notice her obvious cue to kiss her:

Tracy: In China we'd be married by now - or perhaps it's only yesterday.
George: I'm going home after this dance.
Tracy: There was a Chinese poet who was drowned while trying to kiss the moon in the river. He was drunk.
George: I'd say as much.
Tracy: But he wrote beautiful poetry.

Attentively, Mike breaks in and also dances with Tracy, introducing himself: "Macauley Connor of South Bend reporting for duty." Both slightly inebriated, they lurch around the dance area and Mike obviously enjoys spending more time with her. Mrs. Lord joins them when they stop dancing and they all join hands and link together. The would-be bride tells her mother how her outlook has begun to change: "It's just that a lot of things I always thought were terribly important I find now are - and the other way around - and, oh what's the dickens."

Mike also becomes drunk and uninhibited, and decides to take a taxi to Dexter Haven's mansion - to talk to him about Tracy. Totally inebriated at the front door, he loudly calls out: "C. K. Dexter Haven!" Inside, Mike asks Dexter a "personal question" - it reveals his own loving infatuation with Tracy. He has discovered that she is not a "rich, rapacious American female" like he first thought, but a "radiant, glorious queen":

Mike: Are you still in love with her?...Liz thinks you are...But of course, women like to romanticize (hiccup) about things...I don't know, I-I can't understand how you can have been married to her and still know so little about her?...You know, Tracy's no ordinary woman. And you said some things to her this afternoon I resented.
Dexter: Well, I apologize Mr. Connor.
Mike: That's quite all right. Quite all right. But when a girl is like Tracy, she's one in a million. She's, she's sort of like a, she's sort of like a...
Dexter: A goddess?
Mike: No, no, no. No, you said that word this afternoon. No. No, she's, she's sort of like a queen. A radiant glorious queen. And you can't treat her like other women.
Dexter: No, I suppose not. But then I imagine Kittredge appreciates all that.
Mike: Kittredge! Kittredge appreciates Kittredge. Ah, that fake man of the people. He isn't even smart.

Both speak of the scandalous SPY publisher Kidd:

Dexter: I always thought Kidd himself was the five-cent Kidd.
Mike: And what's that make you worth, C. K. Dexter Haven? Bringing us down here.
Dexter: But you know why I did that. To get even with my ex-bride. You told me so yourself...
Mike: Kidd's just using you like he uses everybody else. You don't know Kidd like I know him. The guy's colossal, he's terrific, he's got everybody fooled.
Dexter: No mean Machiavelli is smiling, cynical Sidney Kidd.

They devise a counter-scheme to blackmail Kidd, who allegedly had a "little arrangement in Kansas City," "in San Francisco," and "the time he went to Boston to be awarded the Sarah Langley Medal for World Peace. The true story on that little jaunt would ruin him." Dexter's face lights up, realizing that he can use that information to out-blackmail his scheming editor Kidd, to make the editor think twice about publishing the story about the Lords.

Dexter: You see, Kidd is holding a dirty piece on Tracy's father. This might stop him.
Mike: On Tracy's father?
Dexter: That's right.
Mike: Oh. Oh, so that's how Kidd got you to...That's how Liz and I were gotten in. Blackmail, huh? We all rode into this thing on a filthy blackmail. Well look. You use it. Use it with my blessings. I'm cooked. I'm through anyway. I'm not gonna hand in a story on this wedding. I'm gonna write one on Kidd.
Dexter: No, no. Let me do it. I don't have to tell him where I got my facts, OK?

As Mike dictates his knowledge, Dexter handwrites the story about Kidd - in Boston he entertained "a South Carolina Mata Hari on his yacht." At that moment, Liz interrupts them at the door to pick up Connor, her "wandering parakeet": "We've come for the body of Macauley Connor." She is also taking a semi-conscious Tracy home - she is collapsed in the passenger seat of the car after a fight with Kittredge. Liz describes the conflict they had as a "slight explosion...Fifteen rounds. No decision." Dexter walks over to the car from the front doorway and slides into the driver's seat and rests his head just inches from hers. In an intimate closeup of their two faces, illuminated by the moonlight, her eyes are closed when they begin talking softly to each other:

Dexter: You look beautiful, Red. (She slowly opens her eyes.) Come on in.
Tracy: Why?
Dexter: No particular reason. A drink, maybe?
Tracy: (She gestures negatively) I don't drink.
Dexter: That's right, I forgot.
Tracy: I haven't.

Liz is convinced to stay late at Dexter's place and type up the story on Kidd. Mike takes Dexter's place in the car and Tracy drives them to her home to slip away for a moonlight scene at the Lord's estate. The film's most memorable scene opens with a garden pond-side view of a radio, a champagne bottle, and two champagne glasses. The camera tilts upwards to reveal Mike and Tracy dancing on the edge of the pond - their images are first reflected in the water of the pond. The drink's unusual effects are taking their toll on Mike: "Whiskey's a slap on the back. And champagne's a heavy mist before my eyes." At first, Tracy ignores the incessant ringing of her bedroom's telephone: "It couldn't be anyone but George," then begins running to the house to answer it. When it abruptly stops ringing, she returns to Mike and suggests a quick swim in the swimming pool "to brighten us up."

Mike postpones their swim for a while - first he wants to have a private conversation. As he sits in a lawn chair (with wheels) - that Tracy pushes around in circles on the grass - he sums up his view of Tracy's world in which the rich and privileged class enjoy parties. He argues with her about marrying Kittredge. Tracy accuses him of intellectual snobbery and making specious judgments about people. As she lectures him, she has a change of heart and reveals her most human qualities:

Mike: The prettiest sight in this fine, pretty world is the privileged class enjoying its privileges.
Tracy: You're a snob, Connor.
Mike: No doubt, no doubt...Tracy. You can't marry that guy.
Tracy: George? I'm going to. Why, why not?
Mike: Well, I don't know. I thought I'd be for it at first, but you just don't seem to match up.
Tracy: Then the fault's with me.
Mike: Well, maybe so, but all the same now, you can't do it.
Tracy: No?
Mike: No.
Tracy: Come around about noon tomorrow. I mean today. Snob.
Mike: What do ya mean, snob?
Tracy: You're the worst kind there is. An intellectual snob. You made up your mind awfully young, it seems to me.
Mike: Well, thirty's about time to make up your mind. And I'm nothing of the sort, not Mr. Connor.
Tracy: The time to make up your mind about people - is never. Yes you are, and a complete one.
Mike: You're quite a girl, aren't you?
Tracy: You think?
Mike: Yeah, I know.
Tracy: Thank you, Professor. I don't think I'm exceptional.
Mike: You are though.
Tracy: I know any number like me. You ought to get around more.
Mike: In the upper class. No, no. No thank you.
Tracy (sneering): You're just a mass of prejudices, aren't you? You're so much thought and so little feeling, Professor.
Mike: Oh I am, am I?
Tracy: Yes you am, are you! (She turns on him) Your intolerance infuriates me. I should think that of all people, a writer would need tolerance. The fact is, you'll never - you can't be a first-rate writer or a first-rate human being until you've learned to have some small regard for human fra...(Suddenly, she stops, her eyes widen, and she realizes that she is repeating Dexter's words. She turns) Aren't the geraniums pretty, Professor? Is it not a handsome day that begins, Professor?

Mike doesn't like being called 'Professor,' but Tracy gives little heed to his objection. He then turns the tables. In another exchange, he calls her arrogant and snobbish, but then he tells her that she is magnificent, brilliant and "full of life and warmth" - a real human being "made out of flesh and blood":

Mike: All right, lay off that, Professor.
Tracy: Yes, Professor.
Mike: You've got all the arrogance of your class, all right, haven't you?
Tracy: Halt. What have classes to do with it? What do they matter except for the people in them? George comes from the so-called lower class. Dexter from the upper...Upper and lower, my eye. I'll take the lower, thanks.
Mike: If you can't get a drawing room.
Tracy: What do you mean by that?
Mike: My mistake.
Tracy: Decidedly. You're insulting.
Mike: I'm sorry.
Tracy: Oh, don't apologize.
Mike: Well, who's apologizing?
Tracy: I never knew such a man.
Mike: You wouldn't be likely to, dear, not from where you sit.
Tracy: Talk about arrogance.
Mike: Tracy.
Tracy: What do you want?
Mike: You're wonderful. (She laughs) There's a magnificence in you, Tracy.
Tracy: Now, I'm getting self-conscious. It's funny. I- (She looks up) Mike? Let's...
Mike: Yeah?
Tracy: I don't know - go up I guess, it's late.
Mike: A magnificence that comes out of your eyes and your voice and the way you stand there and the way you walk. You're lit from within, Tracy. You've got fires banked down in you. Hearth fires and holocausts.
Tracy (turning toward him): I don't seem to you made of bronze?
Mike (takes her in his arms): No, you're made out of flesh and blood. That's the blank, unholy surprise of it. Why, you're the golden girl, Tracy, full of life and warmth and delight. Well, what goes on? You've got tears in your eyes.
Tracy: Shut up, shut up. Oh, Mike, keep talking, keep talking. Talk, will you?
Mike (he loosens his hold on her): No, no. I-I've stopped.
Tracy: Why? Has your mind taken hold again, dear Professor?

After Mike comes to his senses after their tipsy emotions have swept both of them away, he asks if she only thinks of him as "Professor":

Mike: It's really all I am to you, is it?
Tracy: Of course, Professor.
Mike: Are you sure?
Tracy: Why, yes, yes, of course...

Mike's forceful, passionate kiss stops her next word. She happily takes the melodramatic kiss and afterwards exclaims softly: "Golly." She takes a breath and kisses him a second time. Then, she stands in his arms, her cheek against his chest, overwhelmed and amazed at herself and starting to shake: "Golly, Moses."

Tracy: All of a sudden, I got the shakes.
Mike: It can't be anything like love, can it?
Tracy: No! No! It mustn't be. It can't.
Mike: Would it be inconvenient?
Tracy: Terribly. Anyway, I know it isn't. Oh Mike, we're out of our minds.
Mike: And right into our hearts.
Tracy: That ought to have music.
Mike: It does, doesn't it? Tracy, you're so lovely.
Tracy: Oh, it's as if my insteps were melting away. What is it? Have I got feet of clay or something?
Mike: Tracy...
Tracy: It's not far to the pool. It's just over the lawn and in the birch-grove. It'll be lovely now.
Mike: Tracy, you're tremendous...
Tracy: Put me in your pocket, Mike.

They proceed to the swimming pool for a post-party (nude??) swim. Early the next morning, Dexter drives a sleepy Liz back to the Lord's house - "home after a hard day's blackmailing." Liz believes the blackmail story will be in Mike's best interest: "Mike's only chance to ever become a really fine writer is to get fired." Liz is in love with Mike but evasive on the subject of marriage: "He's still got a lot to learn. I don't want to get in his way for a while." Dexter thinks her strategy is risky:

Dexter: Suppose another girl came along in the meantime?
Liz: I'd scratch her eyes out, I guess, that is, unless she was going to marry somebody else the next day.

While looking for Tracy (again!) and worried because she didn't answer her phone, Kittredge strolls over to Dexter on the terrace and wants to know why he is there. When Dexter looks down at the table and sees Tracy's engagement ring and bracelet and two unfinished glasses of champagne, he quickly glances in the direction of the family swimming pool - and then advises George to go to bed.

A moment later, Mike's off-camera voice is heard singing the fanciful Over the Rainbow. He appears from the garden wearing a bathrobe and carrying a similarly-garbed Tracy in his arms (she has her arms around his neck). She raises her left leg in rhythmic unison. George is immediately incensed and jealous - he scarcely believes that they just took an innocent swim in the pool, and imagines the most compromising explanation and implications for their behavior:

Dexter: (To George) Now easy old man! (To Mike) She's not hurt?
Mike: No, no.
Tracy: Not wounded, sire, but dead.
Mike: It seems the minute she hit the water, the wine hit her.
George: Now look here, Connor.
Dexter: A likely story, Connor.

Tracy lifts her head limply and greets all three men in various tones: "Hello, Dexter. Hello, George. Hello, Mike." Mike proceeds to take her upstairs to her bedroom, as Dexter ponders: "How are the mighty fallen! But if I know Tracy - and I know her well, she'll remember little of this. For the second time in her life, she'll draw quite a tidy blank." During Mike's brief absence, Dexter (who "pretends" not to believe what he has just witnessed) has an altercation with George over their differing interpretations. When Mike returns, George is about to hit Mike, but Dexter runs interference and doesn't make matters any better when he sends an uppercut to an unsuspecting Mike's jaw first:

George: Hey listen! What right have...?
Dexter: A husband's, till tomorrow, Kittredge.

Apologetic after George leaves, Dexter explains to Mike: "I know. I know. I'm sorry. But I thought I'd better hit you before he did. He's in better shape than I am." The scene concludes as the camera tilts upwards - Dinah has overheard and observed everything from an upstairs bedroom window - the crooning of Over the Rainbow, a man (not Tracy's beau) carrying her sister in his arms after nighttime skinny-dipping?, an argument between her sister's beau and her ex-husband, and Dexter's punch.

Later in the morning (on Saturday, the wedding day), Dinah retrieves a hung-over Uncle Willie (wearing a morning coat, fancy waistcoat and Ascot) in a pony cart and brings him to the Lord's estate. She is anxious to tell him everything she saw that occurred late in the night and into the morning: "Isn't my duty to tell George?...If she marries anyone, it's just got to be Mr. Connor." Dexter steps forward from behind a porch column and asks Dinah if it's possible she has only dreamed what she believes she has seen and heard, but she confirms: "It wasn't any dream." Tracy (also with a tremendous hang-over and squinting at the bright sun) comes out of the house: "I don't know what's the matter with me. I must have had too much sun yesterday. My eyes don't open properly." She wishes Dexter would go home, but Dexter intends to stay - at least until her eyes are opened - literally and figuratively.

Tracy is puzzled and confused that it is so late (nearly half-past twelve), and she appears to have no memory of the previous evening's chaos. She can't understand Uncle Willie's presence in formal wear, and why all the wedding plans (with the orchestra and minister) are so far along. She is confused by a wrist watch [Mike's] she found on the floor in her room and she claims she was robbed of her bracelet and engagement ring that she wore to the party. Dexter produces the two items from his pocket, making her even more puzzled than ever. He suggests that she should have taken a swim after the party, causing her eyes to open wide:

Dexter. You should have taken a quick swim when you got home.
Tracy: A swim? A swim!
Dexter: There, now they're open.
Dinah: That was just the beginning, and it was no dream!

Dexter suggests going to look for "eye-openers" in the pantry. As they leave, Uncle Willie exclaims: "That's the first sane remark I've heard today. Come along, Dexter. I know a formula that's said to pop the pennies off the eyelids of dead Irishmen." Dexter suggests that it might be a good idea if Dinah were to recount her dream to Tracy while he is gone: "If the conversation should lag, you might tell Tracy about your dream." Dinah is worried by the thought of Tracy getting married and going away, so she describes the events surrounding the late-night pool swim. Tracy is quickly alarmed by the embarrassing implications of what Dinah has seen in her surrounding grown-up world:

Dinah: I dreamed I got up and went over to the window - and guess what I dreamed I saw coming over out of the woods?
Tracy: I haven't the faintest idea. A skunk?
Dinah: Well, sort of - it was Mr. Connor.
Tracy: Mr. Connor?
Dinah: Yes, with his both arms full of something. And guess what it turned out to be?
Tracy: What?
Dinah: You, and some clothes. Wasn't it funny? It was sort of like as if you were coming from the pool.
Tracy: The pool? I'm going crazy. I'm standing here solidly on my own two hands and going crazy. Then what?
Dinah: And after a while, I opened my door a crack and there he was in the hall, still coming along with you, puffing like a steam engine. His wind can't be very good.
Tracy: Then what?
Dinah: And you were sort of crooning.
Tracy: I never crooned in my life.
Dinah: I'm only saying what it sounded like. And then he - guess what?
Tracy: I couldn't possibly.
Dinah: Then he just sailed right into your room with you, and that scared me, so I got up and went to your door and peeked in to make sure you were all right. And guess what?
Tracy: What?
Dinah: You were. He was gone by then.
Tracy: Gone? Of course he was gone - he was never there!
Dinah: I know, Tracy.
Tracy: Well, I should certainly hope you did.
Dinah: I'm certainly glad I do, because if I didn't and in a little while I heard the minister say, 'If anyone knows any just cause or reason why these two should not be united in holy matrimony,' I just wouldn't know what to do. Dexter says it's a dream too.
Tracy: Dex-, you told Dexter all that?
Dinah: Not a word. Not a single word. But you know how quick he is.
Tracy: Dinah Lord, you little fiend, how can you stand there and...?