Take a look @ more promo footage from Season 2 of "Marvel's Agent Carter", featuring the return of Marvel's 1940's-era Russian 'Black Widow' 'Dottie Underwood' (Bridget Regan):
"Oh, she's a slippery bitch," said Atwell about 'Black Widow'.
"We haven't seen the last of her. 'Peggy' has male baddies that she fights, but to have someone who is physically her equal -- she's a 'Black Widow', incredibly capable and very smart --
"I think that shows some balance for Peggy, like a flip side of the same coin.
"You'll see more of her in Season 2."
In Season One, Dottie, a product of the 'Black Widow' program, worked alongside 'Dr. Ivchenko' (Ralph Brown) in order to locate a vial of 'Captain America' 'super-soldier' blood, obtained by 'Howard Stark' (Dominic Cooper), but Peggy unwittingly allowed Dottie to escape...
Click the images to enlarge and Sneak Peek 'Marvel's Agent Carter"...