Keira Knightley is no stranger to filming movies on a boat. But The Woman in Cabin 10—her new Netflix thriller that began streaming today—was the Oscar-nominated actor’s first time filming on a $150 million luxury superyacht. And as it turns out, that was much more difficult than filming on a pirate ship.

Based on the 2016 mystery thriller novel by Ruth Ware, The Woman in Cabin 10 was directed by Simon Stone, with a screenplay written by Stone, Joe Shrapnel, and Anna Waterhouse. Knightley stars in the lead role, as an investigative journalist who smells something fishy in the waters on a luxury yacht cruise for charity. Also starring Guy Pearce, Art Malik, Gugu Mbatha-Raw, Kaya Scodelario, Daniel Ings, and Hannah Waddingham, The Woman in Cabin 10 takes viewers along for the tense, moody, mystery-filled boat ride. But after you read more about The Woman in Cabin 10 filming, you’ll be thankful you weren’t actually on the boat.

Read on to learn more about the The Woman in Cabin 10 filming locations.

The Woman in Cabin 10 was filmed, in part, on a real superyacht known as the Savannah, out on the English Channel in September 2024. More specifically, the boat was often docked in the Portland Harbour, off the isle of Portland in in Dorset, England, according to a local news report.

In a recent interview with Decider, Knightley confirmed that it was “a lot of rain, and really cold, and windy,” while filming.

In that same interview, director Simon Stone added that his actors didn’t quite realize what they were getting into. “I think a lot of the actors who I was meeting with for the film, were like, ‘Oh, great, we get to be on a superyacht! So where are we shooting?’ And I’d be like, ‘Oh, the coast of the south of England in fall.’ And then you see the face drop of like, ‘Oh, this is going to be miserable.'”

The yacht itself—worth an estimated $150 million—was owned by Swedish-Canadian businessman Lukas Lundin, who made his money in mining, diamonds, and oil. Lundin died in 2022, but the legacy of his yacht lives on. Filming on it was no picnic, according to Knightley and Stone.

“We weren’t allowed to touch anything,” Knightley said. “We weren’t allowed to sit on anything. We weren’t allowed to like, walk on the carpet. So we were all just kind of crammed in the middle. We weren’t allowed to eat or drink anything, apart from in tiny little designated areas. It was not quite your image of what your experience of being on a luxury super-yacht might be.”

In fact, Knightley found it much more difficult than the boat scenes she did for the Pirates of the Caribbean franchise.

“You can break the pirate ship,” Knightley explained. “Nobody is telling you not to sit or lean or walk or stand. You can run around, and you can do the thing. Whereas this it’s like, ‘Okay, run because somebody is trying to kill you—but don’t touch the walls!’ It was a particular challenge not breaking anything, and knowing that if you did break something, you’d get a bill for like 200,000 grand.”

Luckily, the film crew didn’t break anything—for the most part.

Stone confessed, “I think we scratched a little bit of the floor, and had to spend a grand on buffing one section of floor. But that was pretty good. We did well. We were well-behaved.”

In addition to shooting for four weeks on the superyacht, The Woman in Cabin 10 also filmed for three weeks on a sound stage. This means some of the interior scenes you see are on the boat were actually filmed on a set, and not on the actual boat.

So there you have it! As it turns out, filming a movie on a superyacht isn’t nearly as fun as an actual cruise on a superyacht.