Halo 5: Guardians aims to shock and surprise players with its story, which dives into Master Chief's mysterious backstory and his convoluted relationship with a new character named Agent Locke, according to franchise development director Frank O'Connor.

"I think we'll have done a good job if people are shocked at the end of the game and surprised by the direction that [we] took," O'Connor said as part of a new Halo 5 video posted in the Halo Channel.

Through a viral campaign, Microsoft has been teasing that Master Chief may not be all he says he is. Locke is charged with hunting him down, but we don't exactly know why just yet.

The nature of the Locke/Chief relationship remains unclear, though it certainly sounds interesting.

Locke actor Mike Colter mentioned previously that he "can't confirm whether he's a friend or foe of Master Chief," but he also offered up some more clues about that relationship. Locke is on a manhunt for Master Chief, however, "...you won't know what the purpose of finding Master Chief is [right away]. Or what will happen if we do find him, what condition he will be in, and where he's at mentally. But I'm sure that'll be a plot twist in Halo 5."

Although Master Chief remains the main character and hero of Halo 5, Locke will also be playable for portions of the game.

Also in the video, senior designer Alex Cutting said developer 343 Industries is hoping to avoid a sophomore slump with Halo 5. "Anyone can get lucky once," Cutting said about the generally positive reception to Halo 4, the first all-new Halo game that 343 developed. "This is our sophomore effort. This is where we prove whether we can really pull Halo off."

Halo 5 launches exclusively for Xbox One on October 27. This week at Comic-Con, Microsoft announced the biggest multiplayer map in Halo history. GameSpot editors Justin Haywald and Mary Kish also got to play with Halo toy guns in a real-life Halo 5 multiplayer match of sorts. Watch the video below.