Prepare for battle!

Showtime has unveiled castings for its upcoming live-action Halo television series, based on the best-selling Xbox video game franchise.

As revealed in November, the show will revolve around Master Chief, the helmeted super-soldier at the center of the game series. Pablo Schreiber (American Gods, Orange Is the New Black) will star as the Spartan commando. There's no word on whether Schreiber's version of the character will remained masked like his video game counterpart.

Joining Schreiber is Australian newcomer Yerin Ha, who will play a newly created character in the Halo universe, Quan Ah. Quan Ah is described as a "shrewd, audacious 16-year-old from the Outer Colonies who meets Master Chief at a fateful time for them both." Ah was discovered during a worldwide casting search and is known for her stage work Down Under.

The Showtime series will follow plots set forth in the games, which focused on the 26th century conflict between humanity and the alien race known as the Covenant. The show will "weave deeply drawn personal stories with action, adventure and a richly imagined vision of the future."

The project will begin production in Budapest, Hungary, in the fall. 

Halo is one of the most popular video game franchises in the world, having sold over 77 million copies and grossed more than $60 billion worldwide since its initial release in 2001.

Kyle Killen (Awake) and Steven Kane (The Last Ship) serve as co-showrunners and executive producers for the drama. The series is also executive produced by Darryl Frank and Justin Falvey for Amblin Television in partnership with 343 Industries, the current developers of the Halo games. Otto Bathurst and Toby Leslie are also exec producing for One Big Picture, along with Scott Pennington for Chapter Eleven and Karen Richards. The effort will be distributed globally by CBS Studios International.

In a nod to the scope that Showtime has in mind for Halo, Kane joined the series as co-showrunner in March as Killen wanted to bring in a second-in-command to help with the Budapest production. Halo, which Showtime described as its "most ambitious series ever," has already replaced directors after Rupert Wyatt departed (citing scheduling conflicts with an unknown other project). Wyatt was poised to helm multiple episodes and exec produce. He was replaced by Otto Bathurst (Black Mirror) and an episode was shaved off Halo's initial 10-episode order. The series was originally announced in 2014, with plans initially for the show to bow first on Showtime before moving to Xbox consoles. It's unclear if that is still in the cards. 

Schreiber is repped by WME, Circle of Confusion and Jackoway Austen. Ah is with Australia's Morrissey Management.