Microsoft has published a new TV commercial for Halo 5: Guardians that dives deeper into the Master Chief vs. Spartan Locke story for the upcoming sci-fi shooter. As we learned in the last TV commercial, the “official” story in Halo 5 is that Master Chief is dead. But that’s not exactly true. This new ad sees Spartan Locke and the rest of Fireteam Osiris setting out to hunt down Chief, who has apparently gone rogue.

“The only thing worse than losing a hero, is watching him turn against us,” the narrator says about Chief.

This commercial will air during this Sunday’s Fear the Walking Dead season finale. Microsoft is buying up premium ad space for Halo this year, as last week’s commercial ran during Sunday Night Football on NBC.

Halo 5 launches on October 27 exclusively for Xbox One. You can learn more about the game’s interesting-sounding story through the Serial-style “Hunt the Truth” podcast series, the second season of which recently started.

In other recent Halo 5 news, the Seattle Sounders MLS team will wear Halo-branded jerseys in their matchup against LA Galaxy on Sunday. In addition, you can now listen to the game’s title song, while Microsoft has confirmed that work has begun on Halo 6.

What do you make of this new trailer? Let us know in the comments below.