Sophia Di Martino (born 15 November 1983) is an English actress known for portraying Sylvie in the Marvel Cinematic Universe television series Loki (2021–2023), which earned her two MTV Movie & TV Awards and a nomination for a Critics' Choice Television Award for Best Supporting Actress in a Drama Series.

She also appeared in the third series of 4 O'Clock Club in 2014 as Miss Parkwood and in the 2015 film Royal Day Out.

She was a regular cast member of Casualty, playing the role of Pauline "Polly" Emmerson from 19 March 2009 until 30 April 2011.

[7] Di Martino won Best Breakthrough Performance and Best Team with Tom Hiddleston and Owen Wilson at the 2022 MTV Movie & TV Awards.

[12] In 2016, Di Martino stated that she has "had relationships with both men and women", that she believes "sexuality is a fluid thing", and that she has "definitely tried on different labels at different points in my life".