In 2011, she made her feature film debut in Captain America: The First Avenger. She played Susan Brown in a BBC Four television adaptation of the John Braine novel Room at the Top in 2012. Also in 2012, she landed the part of Annie Desmond in a mini-series Titanic. She provided the voice for the character Melia in the English dub of the 2011 video game Xenoblade Chronicles. In 2012, she was cast as Rosie in Dancing on the Edge. She starred as Lydia Wickham in the adaptation of Death Comes to Pemberley (2013).
She made a surprise appearance on Doctor Who in the first episode of the seventh series as Oswin Oswald, a guest character, but she debuted as a series regular in the Christmas special episode "The Snowmen" as Clara Oswin Oswald. She plays eleventh's and twelve's Doctor companion until 2015. In 2016, she starred in ITV's drama Victoria.