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