Vanessa Nuala Kirby (born 18 April 1987 or 1988) is an English actress. She made her professional acting debut on stage, with acclaimed performances in the plays All My Sons (2010), A Midsummer Night's Dream (2010), Women Beware Women (2011), Three Sisters (2012), and as Stella Kowalski in A Streetcar Named Desire (2014). Kirby rose to international prominence with her portrayal of Princess Margaret in the Netflix drama series The Crown (2016–2017), for which she won the British Academy Television Award for Best Supporting Actress. She has also taken on roles in the Hobbs & Shaw (2019) action films and the Mission: Impossible film series since 2018. For her performance as a grief-stricken woman in Pieces of a Woman (2020), she won the Volpi Cup for Best Actress and received a nomination for the Academy Award for Best Actress. Kirby has since portrayed Empress Joséphine in the historical drama Napoleon (2023).