The Netflix film is based on Ruth Ware’s book of the same name It’s time to hit the seas with Keira Knightley again. But this time, she’s on a superyacht instead of a pirate ship. “The Woman in Cabin 10,” based on Ruth Ware’s book of the same name, centers on Laura Blacklock (Knightley), a journalist invited aboard a yacht full of the mega-rich to cover a charity event. But, when she swears she sees someone go overboard, she’s gaslit as everyone tells her that all passengers are accounted for.