The Woman in Cabin 10 adapts Ruth Ware's 2016 novel into a psychological thriller directed by Simon Stone, who also worked on the screenplay with Joe Shrapnel and Anna Waterhouse.
Keira Knightley plays journalist Laura "Lo" Blacklock, who boards a luxury cruise yacht for an assignment. One night, she believes she sees a woman fall overboard. The passengers and crew insist that nobody is missing. Lo refuses to abandon what she saw and follows the clues, putting her own safety at risk.
The film makes good use of a setting that is elegant and claustrophobic at the same time. Knightley combines vulnerability with stubborn determination convincingly. The polished surroundings become the stage for a psychological struggle in which perception and reality overlap.
The suspense is less consistent. Too many turns feel forced rather than organically developed. Supporting characters appear and disappear without enough space to become memorable. The opening drags, while later passages sometimes drift into excessive drama.
Still, the film aims for more than a conventional mystery. It considers how readily a woman's account can be dismissed, even when she is certain of what she witnessed. The yacht becomes a useful image of immaculate surfaces hiding deeper fractures: a place that gleams while keeping people trapped.
For a quiet evening on the sofa, The Woman in Cabin 10 offers solid entertainment. It is hardly exceptional, but Knightley and the atmosphere make it worth watching.