Ruby Barker (born 23 December 1996) is a British actress. She was awarded Best Actress at the British Urban Film Festival for her role in How to Stop a Recurring Dream. On television, she plays Marina Thompson in the Netflix period drama Bridgerton. Barker played Mercy and Titivillus in the 2015 National Centre for Early Music production of Mankind. She was discovered by Royal Shakespeare Company director Phillip Breen, who cast her as Mary in the 2016 York Mystery Plays and helped her get signed with an agency. Barker then began to appear on television, landing a recurring role as Daisie in the fifth series of the CBBC teen fantasy series Wolfblood. In 2018, Barker starred as Private Sarah Findlay in Of Close Quarters in Sheffield. She began playing Marina Thompson in the 2020 Netflix period drama Bridgerton. She made her feature film debut in the thriller film How to Stop a Recurring Dream. For her performance, she was awarded Best Actress at the British Urban Film Festival.