The Perfect Couple ending explained: Who was the killer?

The latest in a long line of projects to satirise the super-rich, including HBO’s The White Lotus and film Triangle of Sadness, The Perfect Couple takes place in an idyllic coastal town on the Massachusetts island of Nantucket, and revolves around the wedding of Amelia Sacks (Eve Hewson) as she enters into the wealthy Winbury family.

However, when the body of Amelia's maid of honour washes up on the beach the night before the wedding, everyone becomes a suspect.

It soon becomes clear Merritt's death wasn't just an accident, and that foul play was involved. But with a number of the wedding guests having a motive for killing Merritt, who had been having an affair with Benji's father Tag and had become pregnant, who was it that actually committed the murder?

Read on for everything you need to know about the ending of The Perfect Couple, including how it differs from the book upon which it's based.

The Perfect Couple ending explained: What was Greer hiding?

Towards the end of the penultimate episode of The Perfect Couple, it started to seem as though Greer was the guilty party. After all, she had spent a long time on the phone with criminal Broderick Graham, and Shooter had then sent him $300,000.

The police's working theory was that Greer had hired Broderick to kill Merritt, and had convinced Shooter to pay for it so that he could shield her from blame and claim diplomatic immunity himself.

However, Greer then dropped a bombshell of a reveal - Broderick was, in fact, her brother, and he was desperate for money because of his gambling addiction. As she didn't have access to that kind of money at the time, she asked the wealthy Shooter for a loan.

She was released from police custody, and then revealed a further truth to her family - when she and Tag met, she was a high-end escort, who Tag paid for sex.

She told Tag she was done taking care of everything for everyone, and done with hiding the truth.

Who killed Merritt in The Perfect Couple?

So, if Greer didn't kill Merritt, then who did? Well, in fact it was actually... Abby!

Amelia's mother had brought pills with her, intending to end her life early if the pain of her condition got too much. These pills had then been stolen by Thomas, who had a drug habit and frequently stole pills from his family.

Abby had then used these pills to dose a drink she gave to Merritt on the night of her death, and convinced her to go for a swim.

When Merritt was drowsy and in the water, Abby held her head under, drowning her, before walking back to the house.

The next morning, she made certain to thoroughly clean the glass she had used to drug Merritt, hiding all evidence of her involvement.

Why did Abby kill Merritt?

In the end, the reason Abby killed Merritt was not personal, but financial. She knew that if Merritt had had Tag's baby, this baby would be entered into the family trust fund, making it automatically reset.

Abby and Thomas were soon to inherit millions of dollars from the fund as soon as Will, the youngest Winbury, turned 18. If Tag were to have another child, they would have to wait until that child turned 18 to receive the money.

Thomas owed Isabel, who he was having an affair with, $2.5 million, meaning they needed the money fast.

Did Abby go to jail in The Perfect Couple?

Yes, after Thomas revealed this information to the police, they worked out it was Abby who had killed Merritt to solve their financial woes.

Abby was then arrested at the house as the rest of the family watched on.

Where did we leave Amelia and Greer?

In the final scenes of the show, we saw how all the show's other 'perfect couples' were left arguing - whether it was Will and Chloe, Greer and Tag or Thomas and Isabel.

Amelia and Benji, meanwhile, had settled their argument, but had decided to part ways.

In a scene set in London six months later, Greer approached Amelia, who was now back working at the zoo.

She revealed that she'd been trying to find her for some time, and gave her a copy of her new book, to make sure she was happy with it before it was published. This was because it was about Amelia.

Greer admitted she was happy to get rid of Amelia, but had later realised she was actually just jealous of her. She said that if Amelia didn't hate the book she should give her a call and they could get dinner to talk about it. The book was titled: "Your Move".

How does the Netflix show's ending differ from the book?

There a couple of big changes from Elin Hilderbrand's book of the same name, including the circumstances of Merritt’s death.

In Hilderbrand's book, Merritt’s death is an accident, even though it is indeed Abby who is responsible.

In the novel, Abby crushes up a sleeping pill and mixes it into a drink in an attempt to keep Thomas’s mistress at bay.

However, in a disastrous turn of events, Abby ends up giving the drink to Merritt, who drinks it before cutting her foot on some glass on the beach.

When Merritt washes her foot in the sea, she notices a piece of jewellery that Tag gave her lying on the ocean floor. She dives in to retrieve it just as the sedative begins to work, which leads to her drowning.

Similarly, in the show, Abby is arrested for Merritt’s murder, but in the novel, the death is ruled an accidental drowning.

The Perfect Couple is streaming on Netflix. Sign up for Netflix from £4.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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