Olivia Kate Cooke (born 27 December 1993) is an English actress. She is best known for her role as Alicent Hightower in the fantasy drama television series House of the Dragon (2022–present). In television, she has starred as Emma Decody in the thriller Bates Motel (2013–2017), Becky Sharp in the period drama Vanity Fair (2018), and a spy in the thriller Slow Horses (2022).

In films, Cooke has starred in the horror film Ouija (2014), the comedy-drama film Me and Earl and the Dying Girl (2015), the thriller Thoroughbreds (2017), the science fiction film Ready Player One (2018), the comedy thriller Pixie (2020), and the drama Sound of Metal (2020).