'The Killing' surprised us all once again by escaping cancellation a second time, landing on Netflix for a final run of 6 episodes. At the time, it wasn't entirely clear when production would begin, or where season 4 would pick up from season 3 finale “From Up Here / The Road to Hamelin," but now 'The Killing''s final grounds have been revealed. Find out who we'll meet at a military school murder for 'The Killing''s final Netflix season!

New casting notices for the fourth and final season of the rain-soaked Seattle murder mystery have emerged, revealing four series regular roles for a crime set at a a military school, in addition to two recurring guest roles, one of which will prove to be Sarah Linden (Mireille Enos)'s biological mother!

The role will apparently only last two scenes, though the casting notice describes the 50's-60's woman as having a strong resemblance and insight into her daughter, despite being absent from Sarah's life as she built a happy, well-mannered and stable life with a new, middle-class family.

Elsewhere, producers have begun casting for somewhat androgynous military school head Margaret O’Neal, dishonorably discharged from the military from her involvement in a questionable incident during one of her tours in the Gulf. In addition to her natural discipline, Margaret has a deeply buried maternal instinct, one she has projected instead onto the troubled academy boys she is charged with molding into men.

Next up is wealthy family black sheep recruit Cameron Stanton, who comes to bond with Linden, as well as with guest role Kat, a smart girl from the street with reservations about Cameron's affluent family status. We'll also meet A.J. Fielding, Cameron’s charismatic, over-achieving, attractive classmate, with a penchant for manipulating weaklings under his wing.

Finally, we have the third academy student, Lincoln, enrolled at the academy following an alleged attempt to sexually assault a female teacher at his former high school. “He not only chafes under the rule of academy administrator [O’Neal] but is openly hostile to any of the weaker and smaller male cadets, anything or anyone perceived as even remotely feminine is to be derided and destroyed.”

Of course, even against 'The Killing' season 4's military school backdrop, we have to wonder what became of the relationship between Holder and Linden after the season 3 cliffhanger saw the latter gunning down her serial killing former partner in cold blood, against Holder's advice. At least season 4 doesn't start with Linden behind bars, that we know of!

Well, what say you? Are you on board for 'The Killing''s fourth and final season, and its military school backdrop? Who would you suggest for any of the roles outlined above? Give us your thoughts on 'The Killing''s move to Netflix in the comments below!

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