The Woman in Cabin 10: The Truth Behind Its Connection to Ruth Ware’s Bestseller

Netflix sets sail with The Woman in Cabin 10, a nerve-jangling psychological thriller from director Simon Stone based on Ruth Ware’s bestseller; Keira Knightley stars as travel journalist Lo Blacklock, whose luxe cruise trip spirals into claustrophobic paranoia and danger.

Netflix is loading up a glossy nightmare at sea with The Woman in Cabin 10, the hit Ruth Ware thriller that made a lot of readers sleep with the lights on. Think: luxury cruise, limited suspects, and a protagonist who might be right, might be spiraling, or both.

The basics

• Title: The Woman in Cabin 10
• Release date: October 10, 2025
• Where to watch: Netflix
• Director: Simon Stone
• Cast: Keira Knightley, Guy Pearce
• Based on: the 2016 bestseller by Ruth Ware (she gets the modern-day Agatha Christie label a lot)

The setup

Keira Knightley plays Lo Blacklock, a travel journalist who scores the assignment everyone in her field wants: a swanky maiden voyage on a boutique cruise ship. The job goes sideways when Lo sees what she believes is a woman thrown overboard in the middle of the night. The problem: the crew swears every passenger is present and accounted for. From there, it is classic paranoia fuel — Lo pushing to prove what she saw while everyone around her treats her like she imagined the whole thing.

Ruth Ware watched her page-turner turn into a movie

Ware hit a special London screening and told People that seeing her work on screen was as weird and wonderful as you would expect. The first viewing knocked her back; visiting set is what really made it real. Inside baseball detail: she says she is often the last to know how her adaptations are moving along, even though multiple books are in the works. That includes her 2015 debut, In a Dark, Dark Wood, which Deadline has reported is being developed by Reese Witherspoon and producer Bruna Papandrea.

"Honestly, like an out-of-body experience. It was really crazy seeing it when I watched the film for the first time... That was honestly just the craziest thing of my life. It was surreal."

Keira Knightley as Lo: not how Ware pictured her, but it works

Ware admitted Knightley was a surprise when she first heard the casting — not because of talent, but because she always imagined Lo as more of an everywoman than someone traditionally glamorous. That said, she thinks Knightley nails the character: anxious and vulnerable on the surface, but stubbornly tough underneath. If you have read the book, that combo is the whole ballgame.

About the adaptation

Simon Stone is directing, and Ware sounds confident he can thread the needle between stylish thriller and psychological freefall. Between the pedigree of the source material and Knightley leading the charge (with Guy Pearce in the mix), this one has the right pieces for a sleek, locked-room-at-sea mystery. Mark October 10, 2025 if you are in the mood for high-end dread on the high seas.