'Captain America' star Hayley Atwell will return as Marvel's 'Agent Carter' as soon as tomorrow's 'Agents of S.H.I.E.L.D.' season 2 premiere, but Peggy's spinoff series may yet upstage ABC's 'Avengers'-adjacent drama. The latest to join the cast of 'Agent Carter' is none other than 'Boardwalk Empire' and 'True Detective' star Shea Whigham, ostensibly the show's male lead.

Per Deadline, Whigham will take the role of the tough but fair-minded Strategic Scientific Reserve (SSR) Chief Roger Dooley, who himself oversees agents Carter, Thompson (Chad Michael Murray) and Sousa (Whedon favorite Enver Gjokaj). Earlier reports of the character describe Dooley as hardworking, principled, and bothered by ongoing problems in his personal life as well as the challenges of his day job.

Whigham also joins the series' other most recent addition, that of James D'Arcy in the role of Stark butler Edwin Jarvis, a precursor to the 'Iron Man' and 'Age of Ultron' AI character. Its pilot to be directed by one-shot helmer Louis D'Esposito, with 'The Winter Soldier''s  Russo brothers helming the second and third episodes, and 'Captain America''s Joe Johnston likely the fourth, here’s how Marvel describes ‘Agent Carter’:

Marvel’s ‘Agent Carter,’ starring Captain America’s Hayley Atwell follows the story of Peggy Carter. It’s 1946, and peace has dealt Peggy Carter a serious blow as she finds herself marginalized when the men return home from fighting abroad. Working for the covert SSR (Strategic Scientific Reserve), Peggy must balance doing administrative work and going on secret missions for Howard Stark all while trying to navigate life as a single woman in America, in the wake of losing the love of her life–Steve Rogers. Inspired by the feature films ‘Captain America: The First Avenger’ and ‘Captain America: The Winter Soldier,’ along with the short ‘Marvel One-Shot: Agent Carter.’

'Agent Carter''s eight-episode season likely makes it a bit easier to attract such acclaimed talent as Whigham, but in the meantime, what do you think? Does the latest addition to Marvel's prequel drama have you excited for Peggy's story? Stay tuned for the latest, and tell us what you want to see from Marvel's 'Agent Carter' in the comments!

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