peggy agent carter captain america Viewers who watched the "Captain America" films know plenty about Peggy (Hayley Atwell) from "Marvel's Agent Carter." Photo: ABC/Kelsey McNeal

“Marvel’s Agent Carter” is about to premiere on ABC, but Marvel fans should already know plenty about Peggy Carter (Hayley Atwell) since she’s been a secondary character in many Marvel projects. But it’s understandable if you don’t have time to re-watch both “Captain America” films, the “Agents of S.H.I.E.L.D.” TV series and the “Agent Carter” Marvel One-Shot (one of the studio's direct-to-video short films). So here's a refresher on what you need to know about Peggy Carter before the new show starts Tuesday night:

1. She isn’t a secretary. While “Marvel’s Agent Carter” will show her being treated as a second-class agent, Peggy was instrumental during World War II. In “Captain America: The First Avenger,” she helped with Project Rebirth, the experiment that made Steve Rogers a supersoldier.

2. She loved Captain America. Peggy really did love Steve (Chris Evans), even if their relationship never had a chance. In fact, their relationship is why the men at the SSR (Strategic Scientific Reserve) feel like they can’t let her go. They think they’re doing Steve a favor.

3. She helped end WWII. Peggy was on the mission to defeat the last Hydra base, also known as the Battle in the Valkyrie. While Captain America was the hero who took down the last bad guy, he wouldn’t have been able to get there without Peggy. The mission was one of the final battles of the war.

4. Howard Stark is a friend. Peggy and Howard (Dominic Cooper) worked together during the war and they experienced things no one else knows about during Project Rebirth. They’ve bonded because of this, so it isn’t surprising that Stark turns to her for help. He also was one of the only men around her during the war, so he knows that she is a great agent.

5. She founded S.H.I.E.L.D. In “Captain America: The Winter Soldier,” Steve discovered that although Hydra was now running S.H.I.E.L.D., Peggy started the organization. In the Marvel One-Shot “Agent Carter” (a bonus feature on the "Iron Man 3" Blu-ray), Stark asked her to help him build the organization.

6. She develops Alzheimer’s disease. Steve visited Peggy in the present day in “Captain America: The Winter Soldier.” She had a family, had grown old and was in a nursing home being treated for Alzheimer’s. She was lucid for only a portion of her conversation with Steve before thinking they were back in the 1940s. 

7. She found the first 0-8-4. Viewers didn’t see Peggy’s missions without Steve in the films, but "Agents of S.H.I.E.L.D.” gave a glimpse into the past. Peggy found the first 0-8-4, an alien object of unknown origin, in 1945. She didn’t know that it would be able to give Inhumans their powers.

“Marvel’s Agent Carter” begins Tuesday, Jan. 6, at 8 p.m. EST on ABC with a two-hour premiere. Are you excited to see Peggy in the spotlight? Sound off in the comments section below!