Check out the official Halo Nightfall trailer! Watch it now! Secure your access to Halo Nightfall debuting November 11, 2014 in Halo The Master Chief Collection. Halo Nightfall trailer is a live action series providing insight into the origin and backstory of legendary manhunter Agent Locke (Mike Colter, “The Good Wife”), a pivotal new character in the Halo universe who will play a key role in Halo 5: Guardians. A strange and treacherous world exposes elite UNSC operatives to a much deeper danger.