Xbox Entertainment Studios and Showtime are deep into negotiations on a live-action TV series based on the popular Halo video game. The project is reportedly a high-priority for Microsoft production unit head Nancy Tellem.

Steven Spielberg's Amblin TV has been developing a live-action drama series based on Halo for more than a year. A deal is in place to secure two showrunners who will steer the adaptation with an expansive bible developed by screenwriter Stuart Beattie (I, Frankenstein). Xbox Studios is not aiming for a straight-to-series pickup.

Xbox's goal is to develop Halo as a high-end production, along with a number of other properties for their 48 million subscribers. A deal between Showtime and Xbox is taking more time than usual, because both companies are charting new territory. While details are still being drawn up, the current plan is to have the episodes debut on Showtime before they are available on Xbox.

While Nancy Tellem talked up the new series at Microsoft's NewFront presentation, she did not mention her impending deal with Showtime. The title is considered a prized property at Microsoft.

Both Showtime and Xbox declined to comment at this time. Steven Spielberg will executive produce Halo along with Stuart Beattie and Amblin TV. Xbox Entertainment will produce alongside 343 Industries.