‘There Was a Room of Doom’ (Exclusive)

NEED TO KNOW

• Keira Knightley stars alongside Guy Pearce and David Ajala in Netflix’s The Woman in Cabin 10

• Knightley plays Lo Blacklock, a journalist invited to cover an assignment on a luxury yacht, on which she witnesses a possible murder

• The actress tells PEOPLE the cast and crew struggled with seasickness while filming on the boat

Filming a movie on a yacht comes with its own set of challenges — something Keira Knightley and the cast of The Woman in Cabin 10 know all too well.

The actress, 40, stars as Lo Blacklock, an investigative journalist, in the Netflix adaptation of the 2016 Ruth Ware novel.

When Lo is invited on a luxury yacht for a travel assignment, she thinks it’ll be a nice reprieve from her normally heart-wrenching stories. However, after she witnesses a woman thrown overboard, she realizes she’s in over her head — especially when no one believes her that the woman existed in the first place.

As the majority of the filming took place on a yacht, the cast — which includes Guy Pearce as billionaire Richard Bullmer and David Ajala as Lo’s ex and photographer Ben — struggled the most with one thing in particular: seasickness.

“There was a room of doom,” Knightley tells PEOPLE, referring to one of the rooms in which a glass wall borders a swimming pool, meaning the view was of constantly moving water.

The room served as some of the actors’ green rooms for about three days before director Simon Stone noticed the cast was getting nauseous “after seeing that they couldn’t look anywhere because everywhere they looked it was water,” Knightley says.

“We improved a few logistical things quite quickly because we realized,” Stone says. “But we realized that the actors were happier…,” he adds, as Knightley finishes, “… when they weren’t seasick. When they weren’t vomiting. Funny that!”

Pearce, 58, and Ajala, 39, echoed that sentiment, adding that they were among the most prone to seasickness. Pearce says, though, the yacht was “as gentle as it could be for sensitive people.”

While the perks of being on a luxury yacht may have seemed promising — those glistening halls, impressive ballrooms, incredible amenities — the reality turned out quite different for the cast and crew of The Woman in Cabin 10, who were under tight instructions to not touch anything.

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“We couldn’t really experience or enjoy the yacht as one might because we had a whole film crew with us, and the crew of the yacht were obviously very concerned about the wellbeing and the welfare of the yacht,” Pearce says. “So there was sort of restricted areas we could go and things we could sit on and we couldn’t sit on.”

Knightley adds that because the yacht was built to have 25 crew members and 12 guests, filming was strict and tight — as they needed the 25 crew members to man the boat, 70 movie crew members to film the movie and 20 actors on set.

“Because the boat was so expensive, we weren’t allowed to touch any of the walls, we weren’t allowed to walk on any of the carpets, we weren’t allowed to sit on anything, we weren’t allowed to lean on anything,” she recalls. “So we really were all, for 12 hours a day — because we weren’t allowed on and off either — crunched up against each other. So it wasn’t quite the luxury that I’d been envisaging in my head.”

For Stone, the tight restrictions presented an even more difficult challenge, reminiscent of a “student film” or “guerrilla filmmaking.”

“Nothing was allowed to touch the ground,” he says. “Everyone was holding everything that we were using.”

Still, the cast and crew made the best of it. As Ajala jokes, “We are pretty spectacular, though. We can pretend to look like we’re really enjoying!”

The Woman in Cabin 10 is on Netflix Oct. 10.

Read the original article on People