Fans who came to the screening of Marvel One-Shot "Agent Carter" at San Diego Comic-Con have become the first to watch the action movie starring Hayley Atwell. However, for those who unfortunately could not make it, Marvel has unleashed a clip of the movie that briefly features Peggy Carter leaping into action, AceShowbiz said.

The movie picks up where the events of "Captain America: The First Avenger" left off. In the story, British operative Carter joins the nascent S.H.I.E.L.D. organization and searches for the enigmatic "Zodiac" key. As she does her mission, Carter also battles her boss Agent Flynn, who thinks women have no place in the secret-agent business.

Directed by Marvel Studios co-president Louis D'Esposito, the short film also stars Dominic Cooper as Howard Stark and Bradley Whitford as Carter's sexist and bureaucratic boss.

In an interview with Entertainment Weekly, D'Esposito revealed why Agent Flynn would treat Carter that way. "He knows her background but insults her by saying the only reason why she's gotten anywhere is because she was the girlfriend of Captain America," he said.

"We know that's not true, but he's intentionally suppressing her and not allowing her to go on a mission when the opportunity arises."

"Agent Carter" will be included as a special feature on the "Iron Man 3" Blu-ray release due out September 24.