From that point onwards, Knightley tells me, Lo is “a dog with a bone—and she won’t let it go.” Cue nifty detective work, endless gaslighting, a murder attempt via swimming pool, and an anxiety-inducing denouement.

Speaking on Zoom—fresh-faced, with her enviable side-parted bob perfectly in place and wearing a delicate white Valentino shirt with a lace collar—Knightley is great company: candid, self-deprecating, and ebullient, someone who’s quick to laugh and kicks up her heels to show me her glittering shin-length gold boots on camera. “They’re extraordinary,” she gushes. “I’m all-in on this outfit.”

Below, ahead of the film’s release on October 10, the aughts-period-drama queen discusses her love of “silly and crazy” red carpet fashion, her and Ben Whishaw’s hopes for Black Doves Season 2, the forthcoming Bend It Like Beckham sequel, and her new children’s book, inspired by life with her two young daughters.

Vogue: Thinking about Official Secrets, Boston Strangler, Black Doves, and now The Woman in Cabin 10, you’ve played a string of characters who are looking to find and expose the truth. What’s drawn you to these sorts of projects?

Keira Knightley: It’s the entertainment factor. I’ve always liked a Miss Marple story, and I’m trying to do that in a more modern, slightly edgier way. This film reminded me of those ’70s thrillers, like The Parallax View or The Conversation—and they normally have these very cool, louche, ’70s male stars. I had that in the back of my mind. It’s my opportunity to do that.

Lo does have that tough, kind of eye-rolling, sardonic vibe.

I liked her certainty. It’s very rare to play characters who are that certain. She made me feel quite powerful, even though she’s having a horrible time throughout the entire film [laughs].