The head of 343 Industries has unveiled new details about Halo 5: Guardians, 'Halo Nightfall,' The Master Chief Collection and that mysterious Spartan we keep seeing.

In Eurogamer's interview with Bonnie Ross, head of 343 Industries, we have learned some amazing details about Halo 5: Guardians and 'Halo: Nightfall,' Ridley Scott's upcoming series for Xbox Originals. Ross explained that the new Spartan character we have seen featured in Halo 5's promotional artwork and in its E3 2014 trailer is named Agent Locke, who will be playing a "key role" throughout this new story. So, who is Agent Locke? Bonnie Ross claims that we will find out in 'Halo Nightfall,' because it will be focused on the origin story of the mysterious Spartan.

Surprisingly, Ross told Eurogamer that the first episode of 'Halo Nightfall' will launch on the same day as Halo: The Master Chief Collection, Nov. 21. The subsequent episodes of 'Halo Nightfall' will be released in what is likely to be weekly installments after The Master Chief Collection debuts.

Ross explains that Master Chief is still the frontman of Halo 5, despite how focused the promotional artwork and trailer were on Locke. The artwork even had the new Spartan at the top of the picture with Chief standing upside down in Locke's reflection. In terms of John-117, Ross had this to say about Master Chief:

"He is human, he's always been human, but at the end of Halo 4 he really is reflecting on who he is and why he exists," Ross said. She also explained that the point of Nightfall is to introduce us to Locke, "So when you end up with Halo 5: Guardians you have an idea of the background of this new character".

"That was very deliberate because the story we want to tell on Xbox One really is an important part and the main part of his hero's journey. It's more about what he's searching for versus what the UNSC is asking him to do.

Similar to how the terminals of the first Halo's Anniversary Edition unlocked a motion comic introducing the story of Halo 4, the terminals of The Master Chief Collection's Halo 2 Anniversary Edition will preview the story of Halo 5.

343 Industries is also adding brand new prologue and epilogue cinematics to the overall Master Chief Collection, which Ross says will "tie you up and leave you on the doorstep of Halo 5."

The company intends to roll out the welcome mat for Halo 5 with Steven Spielberg's upcoming Halo TV series, which is separate from Ridley Scott's project. The Halo TV series is expected to debut sometime in the fall of 2015, coinciding with the expected launch window of Halo 5: guardians.