She is best known for her role as Myrcella Baratheon in the first two seasons of the television series Game of Thrones (2011–2012).

[2] Richardson's first major acting role was her portrayal of Georgina in romantic comedy Miss Conception in 2008.

[3] In 2011, Richardson was cast to play princess Myrcella Baratheon in Game of Thrones.

At the 2014 San Diego Comic-Con, it was announced that the character was returning for the fifth season; however, the official cast list showed that the role had been recast to English actress Nell Tiger Free.

[15] Since appearing on Game of Thrones, Richardson has been cast for roles on several other television shows such as The Sparticle Mystery (2015),[16] Storyland (2016)[17] and My Mother and Other Strangers (2016).