Way back in 2013, when Microsoft was pushing hard into television show development, it was announced that Steven Spielberg was producing a live-action show based on the Halo games. Microsoft's grand plans for TV mastery were scuttled and its President of Entertainment and Digital Media Nancy Tellem even left the company, but Halo remained. The series was planned for a Fall 2015 release on Showtime. Fall 2015 came and went, and folks expected that we'd never see the series again.
This week during the Television Critics Association winter press tour, Showtime President David Nevins promised that Halo is still on the docket. Nevins told TV Guide that the Halo television show is "still in very active development". Does that mean there's a script? Some storyboards? Is it being cast? Nevins wouldn't comment any further.
There have been two Halo live-action projects already. There was the decent web series Halo: Forward Unto Dawn in 2012, covering the early days of humanity's war with the Covenant. In 2014, Halo: Nightfall was released, covering the origin story of Halo 5: Guardians protagonist Jameson Locke (played by future Luke Cage Mike Colter). Locke and the Master Chief even featured in some live-action commercials for Halo 5.
This feels driven more by Showtime. The network has dramas like Homeland, Billions, and Shameless, but it lacks any genre fare, especially a science-fiction action series like Halo would probably become. If Syfy can release The Expanse, I think Showtime could make Halo happen. It's just a matter of when.