Not much has been revealed about Steven Spielberg's Halo TV show at Showtime, but it has been announced that the series' story will not be based on any of the games and likely won't premiere until 2020. The upcoming blockbuster series is an adaptation of the Xbox games that center on Master Chief, who leads humanity in a war against a race of aliens known as The Covenant.
The Halo TV show was announced back in 2013 but wasn't officially greenlit until this year when it was announced that Spielberg's production company Amblin Entertainment, 343 Industries, and Showtime were ordering a 10-episode first season. A Halo adaptation has been in the works before, with a planned movie that ultimately didn't happen in the mid-2000s. Peter Jackson was attached as executive producer and Neil Blomkamp was going to direct; however, the film, which was supposed to be a joint production between 20th Century Fox and Universal Studios, was canned. While the film may officially be dead, the TV series is very much alive... and moving forward.
As reported by Slashfilm, Showtime recently discussed the plan for the upcoming Halo TV series. Two of their biggest announcements was that the show was not going to be based on any story from the video games and that it wouldn't be airing until 2020. Although Master Chief will be a lead character in the series, President of Programming at Showtime Gary Levine stressed that it was important for the show to have a new story. When asked when fans could possibly be seeing Halo on TV, Levine commented, "It’s an enormous undertaking, so I would say probably in 2020".
Anybody who has played the games knows that Halo has elements that could seamlessly translate to a movie or television show. Halo's lore is often made into books and comics, so there is obviously plenty of source material to pull from, especially for an operatic series that Showtime has in mind. It's worth noting that the network said the series won't be a direct adaptation of any one game, but that doesn't mean the story they're going with can't overlap or run parallel with the new series.
Plus, it's unclear if the series' story will even exist in the same continuity as the games, similar to how 20th Century Fox's Assassin's Creed movie is referenced in Assassin's Creed: Origins. If they remain completely separate, then Showtime can retell Master Chief's story and the game franchise's interstellar war in their own way. In either case, Halo fans are undoubtedly excited to finally get a proper adaptation after all these years.