The Perfect Couple Turned an Accidental Drowning Into Murder

Abby Winbury killed Merritt Monaco so a fourth Winbury child would not lock the family trust for another 18 years. That is the last-minute reveal of Netflix’s The Perfect Couple, the six-episode Nantucket wedding mystery that arrived on September 5, 2024.

The killing does not exist in Elin Hilderbrand’s 2018 novel. Showrunner Jenna Lamia and her producers decided television needed a murderer, because a camera cannot sit inside a drowning woman’s head without a voice-over.

Television Could Not Carry an Accidental Drowning

Hilderbrand’s book ends in Merritt’s own thoughts. She has already drunk a spiked glass meant for someone else. She cuts her foot, sees a ring in the shallows, and goes after it as the drug takes hold. Readers are with her when she goes under. Lamia, a longtime Hilderbrand reader, called that last passage moving, then said a TV show cannot live there.

In a book, she said, you can be inside a character’s head in a way you cannot on television. A voice-over walking through the accident, after six episodes of clue-hunting, would not have been enough. Director Susanne Bier was blunter. She told Netflix she likely would not have made the series had the death not been on purpose.

We all agreed right then and there that there needed to be a murderer, and there needed to be a motive for that murder.

Jenna Lamia, showrunner, to Netflix Tudum

Lamia has said Hilderbrand backed the change and told her to write the scripts while Hilderbrand kept the novels. They also added a money plot so Abby’s reason for killing would be sharp, not only jealousy. Bier’s first call to Dakota Fanning, whom she had directed in The First Lady, was an offer to play “a really calculated murderess.” Fanning said yes at once.

Meghann Fahy, who plays Merritt, joked that the dead girl was the part that got her. She prepped by floating face down in pools, because she knew the ocean work was coming. The show that hired her as a corpse had already thrown out the accident that killed the woman on the page.

Abby Winbury and the 18-Year Clock

Fanning’s Abby is pregnant, married to Thomas Winbury (Jack Reynor), and watching him cheat with family friend Isabel Nallet (Isabelle Adjani). Thomas is in debt. The three Winbury sons stand to collect from their father Tag (Liev Schreiber) once the youngest, Will (Sam Nivola), turns 18, a few weeks after the wedding of Benji (Billy Howle) and Amelia Sacks (Eve Hewson).

Merritt is pregnant with Tag’s child. A fourth Winbury would split the money four ways instead of three. It would also restart the clock: the trust would wait until that baby turned 18. Abby decides she will not wait. Fanning described a woman who feels no one is taking care of her, then hears herself say she will secure her future and her child’s future, and gets lost on that path.

Amelia’s mother, who has terminal cancer, brought three euthanasia pills to the Summerland estate. Thomas, who steals guests’ pills for what the show calls prescription roulette, took one and left it in a bedside drawer. Abby finds it, crushes it into orange juice, and sits with Merritt on the beach. She says, “If you want something done right, you have to do it yourself,” then asks if Merritt wants a night swim. In deeper water she holds Merritt’s head under. Amelia finds the body the next morning, on her wedding day.

Lamia has said Abby also wanted into the Beresford, a high-end New York building, and had not married Thomas only for love. The louder problem with the reveal is not the clock. It is that Abby is asked to drown a woman after a season of being snubbed, and the money does the character work the earlier episodes did not. That is the bill for making the kill “crisp.”

What Changed From Elin Hilderbrand’s Novel?

In the novel, Abby is still the person who puts a barbiturate in a drink, but she is aiming at Thomas’s mistress, called Featherleigh on the page and Isabel on the show. She wants the other woman to pass out before another night with her husband. Merritt drinks the glass instead. After a kayak talk in which Tag tells her the affair was a distraction, she throws his ring into the sea, cuts her foot on broken glass, sees the ring in the shallows, and drowns as the drug hits. The police call it an accident. Greer Garrison Winbury (Nicole Kidman), who writes crime novels, works it out and keeps it.

On screen, Abby means to kill Merritt, holds her under, and is arrested. Amelia does not elope. Greer does not pocket the secret. The cast and crew walk through the finale as a fair-play mystery, not as a private drowning.

BOOK VERSUS THE NETFLIX FINALE

Bier said a bride who goes that far toward a wedding while planning to run made for a hugely unsympathetic person on camera, because a show cannot describe her thoughts the way a novel can. The accident-to-murder switch did not only add a villain. It forced Amelia to become more confused and less guilty, and it forced Abby to become a killer Fanning could play on purpose.

The Glass, the Tallow, and a Toxicology Report

Lamia wanted the audience to feel the show had played fair. The clues sit in ordinary business, just loud enough for someone who watches murder mysteries for sport.

FOUR CLUES LAMIA PLANTED IN PLAIN SIGHT

• The glass: In episode 1, Abby washes a glass by hand while police interview her, with a dishwasher a few feet away and a housekeeper she usually summons for smaller jobs.
• The housekeeper: Abby calls for Gosia (Irina Dubova) more than once; Lamia said this is not a woman who just helps out, so the sink scene should stick.
• The tox report: When Greer drinks with Chief Dan Carter (Michael Beach) in episode 4, Merritt’s paperwork shows pentobarbital levels that are way high if you linger on the page.
• The tallow: Abby’s illegal tummy butter, from a sorority sister’s mother, leaves beef fat in Merritt’s hair; tallow is not water-soluble, so it would still be on the shaft after a drowning.

Before Abby joins Merritt on the beach in the finale, she stands on the porch rubbing that butter into her hands while Thomas and Isabel stagger below and Merritt cuts her foot. Lamia said a viewer with Poirot habits might then guess that someone held Merritt’s head under. The drug on the report is a short-acting barbiturate used in euthanasia, which is why a crushed pill in juice can do the work the ocean finishes.

Amelia Ends Up With the Penguins

In the novel, Amelia and Shooter (Ishaan Khatter), Benji’s best man, are going to elope on the wedding day. The show lets them kiss after the ceremony is called off, then sends her away. Bier did not think she should end up with Shooter. She called Amelia a 30-year-old who cannot figure out what she wants and may be marrying so her very ill mother can see her walk down the aisle.

The last scene is the London Zoo. Lamia posted about shooting it. Hewson said she sees penguins, lions, tigers, and bears as Amelia’s companions in the next stretch, and maybe a less complicated man later. Lamia said Amelia is in an information-gathering stage, and that saying yes to Benji was a mistake, not a cruelty. Throw in the death of her best friend, Lamia said, and she cannot blame her for anything she does.

Lamia also named Amelia and Merritt as the perfect couple of the title, the truest love story in the show. Fahy said that friendship is what drew her. Hewson called it a love story about friendship and grief. The murder mystery exists because TV could not hold Merritt’s last thoughts. The thing the writers keep pointing at, once the killer is in cuffs, is a friendship no voice-over would have been asked to sell.

Bier thinks that if Merritt had lived, Benji and Amelia would have married, lasted a few years, and then Amelia would have left. Lamia thinks Amelia might have walked away at the altar, torn because she is, in Lamia’s word, horny for Shooter. Hewson thinks Merritt would have put her in a getaway car. Fahy’s dream version is simpler: Merritt lives, has the baby, and builds the family she wanted. Bier noted the whole family would have exploded once the pregnancy landed, which might have been a fun story too. It is not the story they built, because they had already voted for a murderer.

Your Move, and a Dinner Amelia May Skip

The escort past is Kidman’s idea. She floated it on a Zoom with Bier and Schreiber. They agreed Greer’s confession to the family in the finale should play as comedy, not melodrama. Bier had so much fun that a sound engineer asked her to stop laughing on the take. Lamia wanted Greer to take back her own story rather than live under Tag’s veiled threats. Bier thinks Greer is leaving him. There is too much water under the bridge, she said, and she does not think he would ever be faithful. He stays at Summerland. She goes to New York to write.

The book was supposed to be about Greer as a young escort. Working through that life, Lamia said, Greer sees why she bristled at Amelia: she was jealous of how much Amelia is herself. The manuscript shifts. It still holds Greer’s past, but it sits inside the summer and the young woman who was going to marry her son. The title is Your Move. Six months after the wedding that never happened, Greer finds Amelia with the penguins, asks her to read it, and offers dinner.

Bier and Lamia think Amelia goes. Bier fought to keep the zoo scene when other people wanted it gone. Hewson is firm the other way. People have asked her, and she has said no: Amelia would thank Greer, call the whole stretch of her life a failure, and move on. Kidman has not answered. The ball the title names is still in Amelia’s court, which is a cleaner ending than the elopement the novel had ready.

The Anthology That Still Has No Writer

The murder they invented did the commercial job the accident could not. Netflix said the series took the top spot on the English TV list with 20.3 million views in four days after the September 5, 2024, launch. The next week it logged 21.9 million views and held No. 1. It spent six weeks on the Global Top 10 for English-language series, the first two at No. 1, and added up to 64.9 million views and 331 million hours while it was on that chart. Nielsen’s U.S. TV-set measure put it at 1.91 billion minutes in the premiere week and 1.97 billion the week after.

Netflix also pushed the opening-credits flash mob to Meghan Trainor’s “Criminals,” and that opening-credits dance that split viewers traveled farther than the drowning. Two years of clip accounts still pass around the cake brawl in episode 4, not Abby’s hands in the water. The show people argue about in fragments is a messy wedding. The show they search by name is a murder the book refused to commit.

THE OPENING NUMBERS

• Four-day debut: 20.3 million views, No. 1 on Netflix’s English TV list.
• Second week: 21.9 million views, still No. 1.
• Top 10 run: six weeks on the Global Top 10, 64.9 million views and 331 million hours in that window.
• U.S. TV sets: 1.91 billion minutes in the premiere week, per Nielsen, then 1.97 billion.

On March 12, 2025, a second installment was reported in development as an anthology, drawn from Hilderbrand’s 2024 Nantucket novel Swan Song, with Joanna Calo of The Bear attached to write. Kidman and Bier were to stay as executive producers, with Gail Berman, Shawn Levy, Per Saari, and Hend Baghdady. Netflix declined to confirm it. On August 19, 2025, Calo left, and no new writer was named. Casting notices in May 2026 still described the follow-up as early in development, with no official cast.

FROM KITCHEN TABLE TO A STALLED ANTHOLOGY

1. 2018: Hilderbrand’s first draft kills the bride; editor Reagan Arthur says the wrong person dies; Hilderbrand rewrites the novel in six weeks with the maid of honor in the water, and the book is published.
2. 2019: The project starts as a Fox network pilot under producer Gail Berman before it moves.
3. 2022: Netflix greenlights the series. Hilderbrand, who wrote it at her Nantucket kitchen table, later visits the Cape Cod set in Chatham and watches Kidman play Greer.
4. September 5, 2024: All six episodes land. Merritt’s death is now a murder, and Abby is arrested.
5. March 12, 2025: A Swan Song follow-up is reported, with Calo as writer, as an anthology rather than a Winbury sequel.
6. August 19, 2025: Calo exits. The adaptation stays in early development with no writer attached, and Netflix still has not confirmed a second season.

Hilderbrand has already changed who dies once, on her editor’s instruction, and called the second death better. Netflix changed how she dies, on the medium’s instruction, and got a hit it has not yet turned into another show. The search that still finds this series is the question the novel never asked.

Frequently Asked Questions

Why did Amelia’s name change from Celeste?

The bride is Celeste Otis in the 2018 novel, and Lamia kept that name through many script drafts. The team changed it because Kidman had already played a Celeste in Big Little Lies and they did not want viewers mixing the two; Lamia named the Netflix bride after her niece. They also cut Celeste’s stutter, a large part of the book character, because Amelia already had enough working against audience sympathy.

Was The Perfect Couple filmed on Nantucket?

Hilderbrand wrote the novel at her kitchen table on Nantucket, where she has lived year-round for 30 years, and she advised Lamia on island speech and on the beat-up Jeep Wagoneers she considers the local car. The shoot she visited was in Chatham on Cape Cod. Netflix greenlit the series in 2022, six years after the book came out.

What happens to Abby in the book if she is not arrested?

The police rule an accidental drowning. Greer, using the habits of her own crime novels, works out that Abby spiked the drink meant for Thomas’s mistress. The last pages say the secret resides with Greer and with Greer it will remain until her death; Abby may realize she is to blame, and Thomas never will.

What is pentobarbital, the drug on Merritt’s toxicology report?

It is a DEA Schedule II short-acting barbiturate. At low doses it has been used as a short-term sleep drug and a pre-anesthesia agent; at high doses it is used for hard-to-control seizures and medically induced comas, and it can stop breathing. It also shows up in some assisted-death protocols and is a common veterinary euthanasia drug, which is why a stolen contingency pill can read as a murder weapon once it is in a glass of juice.

What is Swan Song, the book named for a possible second season?

It is Hilderbrand’s 2024 Nantucket novel, the last of that island cycle. Newcomers Bill and Leslee Richardson buy a $22 million summer home, throw big parties, keep two yachts, then watch the house burn as their assistant vanishes. Police chief Ed Kapenash, renamed Dan Carter and played by Michael Beach in season 1, is near retirement; Netflix has not said whether that character would return.

Hilderbrand changed who dies because an editor told her the bride was the wrong body. Netflix changed how she dies because a camera cannot think a drowning. Abby is in cuffs, Amelia is with the penguins, and the Nantucket follow-up still has no writer.