With filming under way on the pilot for HBO's Watchmen, the adaptation has cast two more actors, including the villain of Warner Bros.' Aquaman.

Yahya Abdul-Mateen II and Sara Vickers have both been added to the cast of the pilot in undisclosed roles. Abdul-Mateen II will appear as the iconic comic book villain Black Manta later this year in the DC Extended UNiverse film Aquaman, while Vickers is best known for her roles in The Alienist and The Crown.

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The pair join the ever-expanding cast of Damon Lindelof's television adaptation of the classic Alan Moore/Dave Gibbons comic book series. Yesterday, Tom Mison (Sleepy Hollow) was cast in a lead role for the pilot while DCEU actor Jeremy Irons was cast earlier this week. The cast includes Don Johnson (Django Unchained), Regina King (The Leftovers), Tim Blake Nelson (The Incredible Hulk), Louis Gossett Jr. (Hap and Leonard), Adelaide Clemens (Silent Hill: Revelation), and Andrew Howard (Bates Motel).

Interestingly, Abdul-Mateen II's Aquaman co-star Patrick Wilson previously appeared in the 2009 Watchmen film as Nite-Owl II.  Wilson will play Aquaman's half-brother Orm in a role that will pit him and Black Manta against DC's undersea superhero.

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Showrunner Damon Lindelof has clarified that the upcoming HBO series will not be a straight adaptation of the comic book series or a direct sequel but exist within the same world as the story. If picked up by the premium cable network, the series is expected to premiere sometime in 2019.

(via Variety)