Hayley Atwell (born 5 April 1982) is an English actress who voiced characters in several Big Finish Doctor Who audio stories: Asha in Blood of the Daleks, Eleanor in The Doomwood Curse, Seksa in The Whispering Forest, and President Sheridan Moorkurk in The Sands of Life.
Outside of Doctor Who, Atwell is known for her work in costume dramas, including Mansfield Park with Billie Piper and The Duchess with Keira Knightley. She's also made her mark in more contemporary productions such as the Woody Allen film Cassandra's Dream and as Lucy in the 2009 remake of The Prisoner alongside Ian McKellen. In North America she is best known for co-starring in the mini-series Pillars of the Earth and as Agent Peggy Carter in the 2011 Marvel film Captain America: The First Avenger.
Atwell has gone on to reprise Peggy Carter in Captain America: The Winter Soldier, Marvel's Agents of SHIELD, Ant Man, and the ABC TV series Agent Carter, which debuted in January 2015.