via press release:
The fourth and final season of THE KILLING picks up right after the season 3 finale. As Detective Linden (Mireille Enos) and Detective Holder (Joel Kinnaman) struggle to manage the fallout from their rash actions at the end of last season, they are assigned a new case -- a picture perfect family is murdered, survived only by the son, Kyle Stansbury (Tyler Ross), who was shot in the head during the massacre. Joan Allen guest stars this season as Colonel Margaret Rayne, the headmaster of the all-boys military academy where Kyle attends. The new season also stars Gregg Henry, Sterling Beaumon and Levi Meaden.