Dame Harriet Mary Walter DBE (born 24 September 1950) is a British actress. Her film appearances include Sense and Sensibility (1995), The Governess (1998), Villa des Roses (2002), Atonement (2007), The Young Victoria (2009), A Royal Affair (2012), Star Wars: The Force Awakens (2015), Denial (2016), The Sense of an Ending (2017), Rocketman (2019) and Ridley Scott's The Last Duel (2021). On television she starred as Natalie Chandler in the ITV drama series Law & Order: UK (2009–14), as Lady Prudence Shackleton in four episodes of Downton Abbey (2013–15), in the miniseries London Spy (2015), as Clementine Churchill in The Crown (2016), in Patrick Melrose (2018), as Lady Caroline Collingwood in Succession (2018–2021) and Dasha in the third season of Killing Eve (2020)