‘The Woman in Cabin 10’ Ending Explained: How the Netflix Movie Differs From the ‘Woman in Cabin 10’ Book

Keira Knightley is once again in danger on a boat in The Woman in Cabin 10, the new thriller movie that began streaming on Netflix today.

Based on the 2016 mystery thriller novel by Ruth Ware, The Woman in Cabin 10 was directed by Simon Stone, with a screenplay written by Stone, Joe Shrapnel, and Anna Waterhouse. Knightley stars in the lead role, as an investigative journalist who smells something fishy in the waters on a luxury, superyacht cruise for charity.

Also starring Guy Pearce, Art Malik, Gugu Mbatha-Raw, Kaya Scodelario, Daniel Ings, and Hannah Waddingham, The Woman in Cabin 10 is the kind of movie that will keep you on the edge of your seat for the entirety of the movie’s 92 minute runtime. That said, if you weren’t paying attention, got confused, or are curious about how The Woman in Cabin 10 movie is different from The Woman in Cabin 10 book, you’ve come to the right place. Read on for a break down of The Woman in Cabin 10 movie plot summary and The Woman in Cabin 10 movie ending explained.

Warning: Major Woman in Cabin 10 spoilers ahead. Duh!

The Woman in Cabin 10 movie plot summary:

Laura “Lo” Blacklock (Keira Knightley) is an investigative journalist fresh off a traumatic reporting assignment in which she witnessed one of her sources being murdered. Looking for a break, she decides to cover what she thinks will be a fluff piece on a luxury cruise for charity, hosted by a businessman named Richard Bullmer (Guy Pearce).

Bullmer is raising money for a new foundation dedicated to his rich, dying wife, Anna Lyngstad, a Norwegian shipping heiress with stage four leukemia. Bullmer is escorting the foundation’s board members on his yacht to a fundraising gala in Norway, and wants a reporter to come along to raise awareness for the cancer foundation.

So, Lo boards the yacht and meets the various wealthy board members. Also on the boat, to Lo’s chagrin, is her ex-boyfriend Ben (David Ajala), a photographer who has also been hired to cover the cruise. Drama! In an attempt to avoid speaking to him, Lo ducks into Cabin 10, where she runs into a blonde woman with a hoodie. Lo apologizes, and leaves.

Lo sits down for an interview with Anne Lyngstad. Anne tells Lo that she has stopped all her medications and treatments, and plans to die soon. Before she goes, however, she plans to give a speech at the fundraising gala in which she will announce that she is giving away all of her money to charity, and leaving her foundation to someone who is not her husband. Anne asks Lo to come back and talk to her again tomorrow.

Late that night, Lo is awoken by a scream and sounds of struggle from the cabin next door, aka Cabin 10. She hears a big splash, and sees a body floating in the water. She immediately alerts the crew, and everyone is roused from bed for a headcount. All the crew and guests are accounted for. Lo insists she heard a struggle in Cabin 10, and is told Cabin 10 is empty, with no guests. So who was the blonde woman in a hoodie that Lo saw?

The next day, Bullmer and his guests brush of Lo as seeing things, and urge her to let it go. But she won’t. In the meantime, Anne is being super weird. She forgot that she asked Lo to meet with her, and blames her medication. But wait, didn’t she stop taking her medication?

With the help of Ben’s photographs, Lo figures out who the blonde woman was. She finds DNA evidence—hair—in the Cabin 10 shower drain. It quickly becomes clear that Lo is onto something when an anonymous someone keeps warning her to back off. Said someone pushes her into the yacht’s pool, closes the cover, and nearly drowns her. When Lo gets back to her room, the hair is gone. Someone really wants her to drop this.

When Lo still doesn’t let it go, she is confronted by the blonde woman in the hoodie. The woman begs Lo to drop it, now that she knows she is alive. In a struggle, Lo knocks of the woman’s hoodie, taking the blonde wig with it. With her hoodie down and her head shaved, this woman looks a lot like Anne Lyngstad.

The woman locks Lo in a make-shift prison on the boat. With time to think, Lo figures out what is going on: Bullman killed his wife, the real Anne Lyngstad, because he knew she was going to disinherit him. That’s whose body Lo saw in the water. This woman with the shaved head is now impersonating Anne. That’s why she said the thing about meds, why she didn’t remember to meet with Lo, and why she’s been acting so strange in general.

The woman confirms Lo is right, and reveals her name is Carrie. Bullmer found her using facial recognition software, determined she would be a good match for Anne, and paid her to pose as Anne to sign some legal documents giving the foundation to him. Carrie insists she did not think Bullmer would kill Anne, and only agreed because she needed money for her daughter. It’s revealed in a flashback was not Bullmer’s plan, but happened after Anne discovered Carrie and things spiraled out of control.

Lo tries to convince Carrie to go the police, insisting that Bullmer will kill her after she’s signed the will. Carrie refuses, but she does leave the door open for Lo to escape the boat, while the rest of the guest are off on a day trip. Bullmer’s doctor stays behind with orders to find and kill Lo. He nearly does, but thanks to Ben—who sacrifices himself in a last-minute rescue—Lo escapes. She jumps off the boat and swims to shore.

The Woman in Cabin 10 movie ending explained:

Carrie, posing as Anne, signs the documents giving the foundation to Bullmer. Lo sneaks into the gala, and tells Anne’s body guard (Amanda Collin) everything. Together, with Carrie, they come with a plan to expose Bullmer. At the gala, Carrie—still posing as Anne—calls on Lo to speak. Unable to deny “Anne’s” request in front of all these people, Bullmer lets Lo speak. Lo reads Anne’s original speech announcing she is giving away all her money and disinheriting Bullmer. Carrie-as-Anne confirms that she, Anne, wrote the speech, and that these are her wishes.

Bullmer snaps, attacks Carrie, and announces to the gala that she is not the real Anne. Bullmer puts a knife to Carrie’s throat, and uses her as a hostage to escape the room. Bullmer marches Carrie down the dock to the boat, hoping to escape. Lo and the bodyguard follow, and a fight ensues. For a moment, it seems like Lo will have to watch another person die in front of her. But not so fast—Lo knocks out Bullmer, and saves Carrie’s life.

In the last scene of the movie, Lo is back in the newsroom. Her article was a hit. She receives a video text message from Carrie that reveals Carrie and her daughter are safe. With that, the movie ends. All’s well that ends well.

The Woman in Cabin 10 movie vs The Woman in Cabin 10 book:

The Woman in Cabin 10 movie makes a few changes from The Woman in Cabin 10 book. In the book, the conflict between Anne, Carrie, and Bullmer is more about the fact that Carrie and Bullmer are having an affair, and less about the money. It seems the affair/romance plot line was downplayed for the film, while the inheritance/money plot line was played up.

In the book, Carrie believes she loves Bullmer, and is willing to go along with his plan to let his sick wife die of cancer, with Carrie taking Anne’s place. But when Anne walks in on her husband and Carrie, a struggle ensues, and Bullmer kills Anne. After the murder, Carrie helps Bullmer take Lo prisoner. Bullmer informs Lo’s family that she is dead.

Eventually, Carrie feels so guilty for her involvement, that she goes to Lo, and they come up with a plan. Lo herself dresses up as Anne, and swims to find help. And Carrie is the one to shoot and kill Bullmer. When Bullmer and Anne’s bodies are found, authorities assume Bullmer killed his wife, and then himself. Carrie escapes at the end of the book, uses Anne’s passport to get some of Anne’s money, and wires some of the money to Lo.

Also, in the book, Lo is a travel journalist, not an investigative journalist, and she is much more of an unreliable narrator. Book-Lo was recently traumatized by a burglary and isn’t sleeping well. The reader isn’t sure if what she saw in the water was real, at first. In an interview for film’s press notes, the movie director Simon Stone explained why he wanted to steer the movie version away from this “gaslighting” theme.

“I wanted to lean away from that,” Stone explained. “The audience doesn’t question whether or not this person saw what they saw, they agree completely with her and take it as fact that it’s her struggle against a conspiracy.”

That’s also likely why the movie made Lo an investigative journalist, to give her a more serious job title. “what you want is an inherent respect for the lead character,” Stone said in that same interview. “You also get that gunning for someone, you’re very empathetic. You’re not watching it going, ‘Is that woman crazy or not?’ It’s more like, ‘I am that woman, and I really want her to solve this, and I really want us to get to the end of this.’”