In 2009, Andy reluctantly attends a Hamptons dinner party that her friend and former Runway colleague Emily organized to find investors for their planned wedding magazine, The Plunge. Emily seats Andy beside Max Harrison, whose father recently died and who now runs Harrison Media Holdings. That evening, while others smoke marijuana, Andy and Max slip away to talk. He confides that his father died of alcohol-related causes, not cancer, and that he quit drinking after his father’s drinking spiraled out of control.

The next day, while Emily has other plans, Andy spends a perfect afternoon with Max on his speedboat and at the beach. Over clams, Max reveals that he has read all Andy’s work for the wedding blog Happily Ever After and is impressed. Andy passionately pitches The Plunge as a high-end, Runway-style wedding magazine for sophisticated brides. Max tells Andy that he wants to invest. Before dropping her off, he sets a meeting at the Harrison Media offices to confirm the details. At the meeting a few days later, he commits Harrison Media to a six-figure investment.

They begin dating immediately, spending five intense days together. When Andy tells Emily, Emily reveals that she already suspected. Emily warns that Max has a playboy reputation but thinks he may have changed. At a book party hosted by Harrison Media, Andy meets Max’s mother, Barbara Harrison, who is cold and critical until Andy mentions working at Runway for Miranda Priestly—then Barbara becomes animated and interested. Despite the chilly reception, Max and Andy grow closer, and Andy falls in love.

The narrative returns to Andy’s wedding day. Nina, the wedding planner, leads a shaken Andy back to her suite and encourages her to keep moving forward despite her doubts. Andy’s family and friends arrive—her mother; her sister, Jill; her grandmother; her oldest friend, Lily; Emily; and Max’s sister, Elizabeth—though Andy wonders if Elizabeth, like Barbara, disapproves.

Nina announces it is time to begin and returns the letter she had taken from Andy earlier. Alone, Andy rereads it, then tears it up and flushes it. Nina escorts her downstairs, where her father waits by the ballroom doors. Overwhelmed, Andy briefly considers telling him she cannot go through with it. The doors open, and 300 guests rise.

Andy tells herself that Max loves her and that Barbara’s disapproval does not define their relationship. Steadying herself, she starts down the aisle.

Andy wakes the morning after her wedding. Though the reception appeared flawless, she felt conflicted all evening. The previous night, she got sick, privately attributing her symptoms to anxiety; Max assumed she had too much champagne and was kind, but they did not have sex.

Emily calls excitedly about their wedding announcement in The New York Times. Andy retrieves the paper and reads the glowing account of their credentials, families, and courtship. The mention of Max’s late father reminds her of Max’s deep family devotion. Reading the announcement also makes her think of Alex Fineman, her ex-boyfriend, who was judgmental about her career, unlike supportive Max.

The estate manager brings a celebratory breakfast. Max emerges cheerful and loving. Seeing the announcement, he declares it perfect. He kneels beside her, senses something is wrong, and promises he is there whenever she is ready to talk. Though reassured, Andy still cannot confront him about the letter and decides to push her fears aside to enjoy the weekend.

Andy and Max cut short their post-wedding trip because she is still sick. Back in New York, Andy sneaks out early to The Plunge offices. When Emily calls, Andy tells her about Barbara’s letter and Max seeing Katherine in Bermuda. Emily dismisses it, insisting Max would not cheat and that Katherine is no threat.

At work, the photography director shows Andy the rush-delivered wedding photos. Her office phone rings—it is Max, checking on her. She spills coffee, cries, and they confirm plans for that evening’s Yacht Party, the annual event for Max’s Yacht Life magazine.

At the party on a lavishly decorated yacht, the designer Valentino arrives with Miranda Priestly as his date. Andy panics. When Valentino tries to introduce them, Max says he and Miranda do not know each other, but Miranda contradicts him. Max introduces Andy as his wife, but Miranda has already turned away without acknowledging her.

Shaken, Andy overhears young models discussing Miranda reverently. When one suggests approaching her, Andy reflexively warns them not to. Embarrassed, she admits she used to work at Runway long ago. Feeling nostalgic yet protective, she wishes them well and walks away.

The morning after the Yacht Party, Emily calls Andy before seven. A lawyer from Elias-Clark, Stanley Grogin, wants a conference call with both of them. Andy connects it to seeing Miranda and panics.

The narrative flashes back to 2004, the year after Andy quit Runway. Alex broke up with her and moved to Mississippi. Lily left for Colorado after rehab. Her parents announced their divorce. Feeling alone, Andy freelanced for the wedding blog Happily Ever After and enrolled in a cooking class, where she was shocked to find Emily Charlton, her former Runway colleague.

As kitchen partners, they tentatively reconnected. Emily revealed that Miranda had fired her without explanation four months after Andy quit. Andy confessed that she once wrote Miranda’s obituary as a form of therapy and admitted she still drops Miranda’s name to book celebrities. They bonded over their shared trauma, became best friends, and a few years later conceived The Plunge together. Max became their investor and Andy’s fiancé.

Back in the present, their assistant reaches Grogin, who refuses to explain and demands a conference call with colleagues present. Andy is convinced Miranda is suing them. Emily insists that Miranda wouldn’t bother suing them and has probably forgotten all about them, but Andy feels thrust back into panic, as if the past 10 years had not happened.