The Woman In Cabin 10 has plenty going on, and yet it’s a tightly written film that doesn’t overstay its welcome or rely on its mystery dragging out to keep us hooked. It knows its audience, knows it’s easy to grow tired of watching Laura, or Lo as people call her (Keira Knightley) — an investigative journalist who’s been tasked with covering the maiden voyage of a luxury yacht — be gaslit by every character in the film before needing to move on.

Based on the novel of the same name by Ruth Ware, The Woman in Cabin 10, directed by Simon Stone, who co-wrote the screenplay with Joe Shrapnel and Anna Waterhouse, could have easily become a cliché, but it holds steady in its psychological thriller elements, staying grounded thanks to Knightley’s Lo, who was traumatized watching a woman killed by drowning after she agreed to speak with her for her last major exposé. Lo is a workaholic, as her editor (Gugu Mbatha-Raw) essentially scolds her for, but it isn’t her sole characteristic.

In some ways, Lo’s need for work acts as avoidance, but it also lays the groundwork for potentially disbelieving what she sees later, when a mysterious and unaccounted-for woman goes overboard. Maybe Lo’s been working too hard; maybe she’s just too traumatized by seeing another woman die again. But these are primarily questions for the suspicious rich elite aboard the ship, who have all been invited in honor of Anne Bullmer (Lisa Loven Congsley), who has stage four cancer and whose husband, Richard (Guy Pearce), is throwing a gala for Anne and the foundation before she dies.

The story leans hard into the psychological aspects, though its thrills aren’t so pulse-pounding as they are occasionally gasp-worthy.

Though suspicious of wealthy, powerful people in general, Lo finds herself drawn into their world and even sympathetic to Anne, who requested her presence aboard the yacht. But once the title character is thrown overboard, Lo’s brief moment of letting her guard down with the guests — an ensemble cast including Kaya Scodelario, Hannah Waddingham, Daniel Ings, and David Ajala, who plays Ben, a photographer and Lo’s ex — is over as she begins investigating what exactly happened to this mysterious woman everyone claims was never there.

The Woman In Cabin 10 Keeps Us Hooked By Not Going Overboard

The film, at a little over an hour and a half, never feels rushed. We get the gist of who Lo is and, though the story is very much about the mystery, it’s also a story of redemption for Lo, who feels like a failure after her contact was killed despite getting the story out. While other forms of media tend to somewhat glamorize the rich, The Woman in Cabin 10 holds them at arm’s length. They each have their quirks and personalities, but the story isn’t about them ultimately; it’s about finding the truth.

At one point, Scodelario’s character tells Lo that she’s basically a buzzkill, someone whose penchant for the truth is ruining what was supposed to be a good time. In one sentence, the movie highlights the absurdity of such thought and mirrors our real world. Why stop the party to care about others or learn the truth if it means putting a wrench in the fun? The film treats journalism with a seriousness and idealism that is sometimes only found in movies, but Lo’s need to uncover what the powerful don’t want her to know is admirable, and we root for her every step of the way.

The story leans hard into the psychological aspects, though its thrills aren’t so pulse-pounding as they are occasionally gasp-worthy. Knightley as Lo is exceptional, layering her performance with a sense of exhaustion, dread, suspicion, and perseverance. Her discomfort with Richard and Anne’s friends is instant, and her body language is always on edge, as though ready to grill them or flee at any moment.

The fact that she doesn’t fit in is not played for laughs, but it’s baked into the narrative to give us a sense of how different she is from these people; Lo even overdresses for a dinner that gets her comments and further underscores that she is not of this world but a key part of unraveling it.

As soon as we start growing tired of the psychological game the characters are playing, a major secret is revealed that drives the rest of the story to an explosive but not so over-the-top conclusion. In many ways, the film is hopeful despite the terrible things that happen; the idea that the truth will somehow prevail is optimistic but, at least here, not so misguided that it risks making The Woman in Cabin 10 so unbelievable.

Visually, the film is colored in steely grays, too-pristine, and dimly lit hallways. The yacht, in some instances, feels more like a prison that Lo can’t escape. And yet the film doesn’t dawdle, with Simon Stone utilizing every inch of the space to create a sense of claustrophobic intensity and a feeling of always being watched.

And while the film could have certainly focused a bit more on Lo’s relationship with Ben — which is a touch underwritten, especially with how this plays into the end — it nonetheless works on almost every level. Even when it gets so close to becoming repetitive, it shifts gears, allowing the narrative, and us as the audience, to refocus. From the opening scenes, The Woman in Cabin 10 hooks us and doesn’t let go.

And while I can’t compare it to the book it’s based on, the film mostly and successfully pulls off an intriguing psychological mystery that gets right to the point, leaving the frills behind to tell a tense and engaging story.