This Agatha Christie inspired thriller wants to be clever and suspenseful, but instead it feels sluggish and oddly lifeless.
Journalist Laura “Lo” Blacklock (Keira Knightley) has just returned to work after witnessing a traumatic event the death of a female source. Hoping to ease her back in, her editor assigns her a fluff piece: covering a luxurious new yacht cruise. It’s supposed to be a sort of working vacation, but of course, things don’t go as planned.
The trip is hosted by terminally ill heiress Anne Bullmer (Lisa Kongsli) and her husband Richard, who are throwing a lavish charity gala to announce that Anne plans to give away her fortune. Among the glittering guests are Lo’s ex-boyfriend (awkward), an aging rock star Danny (Paul Kaye), socialite Heidi Heatherly (Hannah Waddingham) and her husband (David Morrissey), influencer Grace Phillips, and Anne’s personal doctor, Dr. Mehta (Art Malik).
But before the champagne glasses can even be refilled, Lo overhears a scuffle in the next cabin followed by a chilling splash in the ocean. She’s convinced a woman has gone overboard, possibly the same one she met briefly the night before. When no one believes her and all the passengers are accounted for, paranoia and tension begin to mount… at least, that’s the idea.
The problem is, the suspense never really takes hold. The script feels flat, as if it’s ticking off mystery tropes without much energy or emotional depth. There’s no real sense of claustrophobia or creeping dread two things a story set entirely on a yacht should deliver effortlessly. Knightley does her best to sell Lo’s unraveling state of mind, but she’s working with dialogue that’s often too on-the-nose. Stone’s direction keeps things tidy when the film desperately needs chaos.
And honestly, what was up with Hannah Waddingham’s Australian accent? She’s such a powerhouse actor, but the choice just didn’t suit the character it felt distracting rather than distinctive.
The Woman in Cabin 10 wants to be a glossy, modern mystery with bite, but it ends up feeling like a cruise you can’t wait to dock from polished on the surface, but with very little depth beneath the waves.