Agent Carter - Marvel Short

Peggy Carter will be back and kicking bad guy's butts in Agent Carter, a short created by Marvel in the same vein as last year's prelude to The Avengers, Item 47.  Peggy Carter, played again by Hayley Atwell, will be after something called Zodiac.

Peggy Carter was the love interest for Steve Rogers in Captain America - The First Avenger.  A planned appearance by Carter (in her 90's) in The Avengers movie never happened but rumor has it she might be in the next Captain America movie, The Winter Soldier.

Agent Carter will debut at San Diego Comic Con.

Sources - ainticool.com and Entertainment Weekly