The Woman in Cabin 10 ending explained: Who was thrown overboard?

Based on Ruth Ware's novel of the same name, Knightley plays an investigative journalist named Lo who is convinced she sees a passenger thrown overboard the luxury yacht she is travelling on – even though everyone aboard claims that nothing is amiss and all the passengers and crew are still accounted for.

As she investigates, things continue to get increasingly suspicious leading up to a major twists – if you've seen it and need it all unpacked, read for The Woman in Cabin 10 ending explained.

The Woman in Cabin 10 ending explained: Who was thrown overboard?

As Lo’s paranoia grows, it’s starts to become apparent that she was right to be fearful of the rest of the guests on the boat, as she was right all along.

After discovering that the woman she had seen in the supposedly unoccupied cabin (number 10) is actually the spitting image of Anne (Lisa Loven Kongsli) things start to click into place.

Richard (Guy Pearce) had invited this doppelgänger, Carrie (Gitte Witt), to the maiden voyage of his luxury yacht to temporarily switch places with his wife, Anne, so she could change Anne’s will to leave everything to him.

However, in Agatha Christie-style fashion, nothing goes to plan. It’s revealed when Anne discovered Carrie and her husband scheming in cabin 10, a fight broke out, and she fatally hit her head, before Richard pushed Anne overboard. Horrified, Carrie does as Richard tells her and becomes Anne for the rest of the trip.

Carrie confides all of this to Lo when she traps the inquisitive journalist in a storage room (as Lo realises quickly that the woman she saw in cabin 10 was Anne or someone who looked like her). Lo is missing for several days, which Dr Robert Mehta (Art Malik) along with Richard cover up as illness, checking in on Lo and keeping a growingly concerned Ben (David Ajala) at bay.

When everyone leaves the ship for the day, apart from Ben who feels bad for leaving Lo (his ex-girlfriend) behind, Robert sets out to look for Lo in every corner of the ship. He doesn’t find her, but as the boat quietens down, Lo escapes from her hidden room to go up to Anne’s study, find the hidden key and steal her confession from her desk drawer – the one Anne had read her several days before.

As Lo descends back down towards her cabin, she’s stopped by Robert, who blocks her way and has a syringe in hand to silence her once and for all. Lo fights him off, as the duo scrap on the floor and Robert tries to strangle her, before Ben appears and fights Robert off Lo.

In the altercation, Robert accidentally injects Ben with the lethal syringe, much to Lo’s horror. As he shouts at her to run even though Lo is too distressed to leave him, Ben continues to fight Robert off, until he collapses on top of him and dies.

Thanks to Ben’s help, Lo manages to rush back into her room and leap off her balcony into the icy waters below. Manically, she swims to shore and hides a shed and starts a fire to keep warm.

Robert – who has always been in on the fraudulent scheme as Richard holds something over him – tells Richard that there’s no way Lo could have survived the freezing temperatures of the water, and they assume that she’s died in her attempt to escape.

Richard takes the fake Anne (Carrie) to meet with their lawyers to rewrite the terms of Anne’s so that upon her death everything isn’t given to charity, but her greedy husband, Richard. Carrie has no choice but to sign on Anne’s behalf, despite being torn about how disposable she’ll be after the gala (as Lo warned her).

Carrie hides her doubts and gets ready for the gala to pretend to be Anne for one more night. During the preparations, Lo gatecrashes the event and is stopped by one of the members of the crew. Lo asks if she’s seen a change in Anne’s behaviour, before revealing the truth that it’s a doppelgänger and proves it by letting her read the speech Anne wrote.

She allows Lo to stay and mid-way through Richard’s speech, dedicated to his wife, Lo enters the room full of people saying she has something that Anne would want her to read. Carrie (as Anne) gives her permission for the letter to be read, despite Richard’s attempts to throw Lo out, as even his wealthy friends (and the guests who didn’t believe Lo’s wild theories on the boat) remind him that this gala is in honour of Anne, so she should be allowed to speak.

Lo reads the speech that the real Anne prepared for the gala, the one where she revealed that she wanted to give her fortune away, rather than leave it to her husband. Richard becomes more distressed, but he can’t challenge what Lo says as then he’d have to admit the truth: that he killed the real Anne and replaced her with the fake next to him.

As Lo reads more incriminating words, Richard panics and takes Carrie hostage at knifepoint to flee from the scene and heads along the docks and back towards a lifeboat. In the tense moment, Lo’s new ally, the member of the crew, shoots Richard in the shoulder. He becomes desperate and tries to strangle Carrie, before Lo finishes him off with one fatal blow with a x and he falls to his death.

Carrie and Lo embrace, now free from this wicked scheme. In a fast forward, we see that Carrie is now reunited with her family, as she sends Lo a video to invite her to visit them. Meanwhile, Lo has published her expose in The Guardian about Anne’s charitable final act, her legacy and the fateful events on the ship.

A younger journalist compliments Lo on her making the story a tribute to Anne, as opposed to solely about Richard’s actions instead. Her article is also a tribute to her late ex, Ben, who heroically saved her from being silenced on the ship, and it also details the two-remaining co-conspirators at large, Robert and the Captain, John (John Macmillan).

In true Lo fashion though, she’s straight back to work, but not before one final smile at her screen at the picture of Ben.

The Woman in Cabin 10 is now streaming on Netflix. Sign up for Netflix from £5.99 a month. Netflix is also available on Sky Glass and Virgin Media Stream.

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