The film, like the book, follows Lo Blacklock (Knightley), a journalist who boards a new luxury yacht, the Aurora. The yacht is also housing a number of VIPs, played by the likes of Waddingham, and it seems one of them may be a murderer. You see, Lo thinks she’s witnessed the aftermath of a murder. The victim? A woman staying next door to her in cabin 10. The problem? There’s no record of this woman ever being a passenger on the ship.
Changes between the book and the film abound right from the get-go (why Lo is on the boat, the professions of the other characters, how she meets the woman in cabin 10). But perhaps the biggest difference is that Knightley’s Lo is wildly different than the one in the novel. Hers is much more successful, confident, flirty and, well, less trauma-driven (at least to begin with). It’s a jarring change, but honestly, it makes the character much easier to watch and root for. The Lo of the novel is more akin to lead characters in The Woman in the Window and The Girl on the Train. The Lo of the film is an award-winning journalist without the same level of crippling anxiety. It’s still a complicated role for Knightley to tackle (it is revealed her Lo previously witnessed something horrific), but one that’s much more palatable in terms of a movie heroine.
This “together” initial character also gives Lo more room to change once things start going awry (AKA when she thinks sees someone from cabin 10 go overboard).
