Peggy Carter/MCU

Margaret "Peggy" Carter is a fictional spy and a key figure in the continuity of the Marvel Cinematic Universe. Played by actress Hayley Atwell, she was introduced as a supporting character in the 2011 feature film Captain America: The First Avenger. Atwell reprised the role as an aged Peggy Carter in a brief scene in the film's 2014 sequel, Captain America: The Winter Soldier. Peggy Carter was also the main focus of the film short "Marvel One-Shot: Agent Carter", which spun-out into the 2015 Agent Carter miniseries on ABC. Peggy Carter appeared in all eight episodes of the series.