‘Agents of S.H.I.E.L.D.’ premiere guests will include Hayley Atwell and George Stephanopoulos

(CBR) Hayley Atwell and George Stephanopoulos are set to guest-star on the season two premiere of “Agents of S.H.I.E.L.D.”

The synopsis of the “Agents of S.H.I.E.L.D.” season two premiere, “Shadows,” was full of new details for the show's return to ABC — and while there were a number of known actors listed in the guest-star section, two names in particular stand out: Hayley Atwell, star of Marvel's upcoming television series “Agent Carter,” and famous politician George Stephanopoulos.

Fans of the Marvel Cinematic Universe should be incredibly familiar with Atwell — as Agent Peggy Carter, the actress appeared in “Captain America: The First Avenger,” “Captain America: The Winter Soldier” and the Marvel One-Shot “Agent Carter.”

The “Agent Carter” TV series, which airs later this season on ABC, will focus on the character's life after “The First Avenger,” as she helps to establish the organization of S.H.I.E.L.D. The synopsis did not indicate whether Atwell would appear in flashback to the early days of S.H.I.E.L.D., or in the present day as seen in “The Winter Soldier.”

Given the political implications of Hydra infiltrating the inner and upper ranks of S.H.I.E.L.D., George Stephanopoulos appearing as himself is an intriguing choice. Stephanopoulos, an American television journalist, was the White House Communications Director during the Clinton administration and is currently a member of the Council on Foreign Relations.

Stephanopoulos is actually no stranger to scripted television, having appeared previously on “Spin City.” As the current ABC News Chief Anchor, there are certainly many ways that he could appear on “Agents of S.H.I.E.L.D.” — though, like Hayley Atwell — the finer details of his appearance were kept under wraps.

“Agents of S.H.I.E.L.D.” returns to ABC on September 23.