Sharon Carter was a S.H.I.E.L.D agent. When S.H.I.E.L.D. fell, she then joined the CIA. Her main undercover identity was as a nurse which she was in when she first met Steve Rogers. She is also the neice of Agent Carter who worked closely with Steve during World War II.
Marvel Cinematic Universe
Sharon Carter is the great niece of legendary S.H.I.E.L.D. founder and Director Peggy Carter. Following in her aunt's footsteps, Carter became an agent of S.H.I.E.L.D., although she never revealed her relation, not wanting to be put under the pressure of living up to any expectations.
Under direct orders from Nick Fury, she was tasked with going undercover as a nurse, living next to Steve Rogers. When Fury was attacked, she blew her cover to Rogers. When HYDRA was revealed to have been operating within S.H.I.E.L.D., Carter chose to stay loyal to her organization, and fought during the Battle at the Triskelion, facing off against Brock Rumlow to protect millions of lives.
In the aftermath of the HYDRA Uprising, Carter left the disbanded S.H.I.E.L.D. and joined the CIA, before being stationed at the Joint Counter Terrorist Centre. In 2016, her aunt passed away, and Carter gave a eulogy, where she revealed her true identity to Rogers. When the Vienna International Centre was bombed, Carter returned to the JCTC after giving Rogers information on Bucky Barnes. When Barnes was arrested about brought to the JCTC, Helmut Zemo reactivated his mental programming, causing Carter to try and stop him, to no success. She later assisted Rogers in handing over his team's equipment, which would indirectly spark the devastating Avengers Civil War. Her involvement in helping Rogers would cause Carter to go on the run.
In 2018, when Thanos obtained all of the Infinity Stones, he snapped his fingers, wiping out half of all life across the universe. Carter was amongst the victims in this catastrophic event, suddenly turning to dust. Fortunately, five years later, after the Avengers stole the Infinity Stones, Bruce Banner successfully brought everyone who had died back to life, returning to where they had disappeared.
- She uses the same face as Leia's 2015 Endor variant redesign.