A rogue AC enters Forthaven and ends up attacking one of the citizens which prompts the PAS officers to take action in an effort to control the situation.

When missing expeditionary Josie Hunter walks back into the settlement, unharmed, the jubilant air quickly takes a darker tone. Josie is different, her children cannot communicate with her, and reports of her violent behaviour circulate. Tate and Stella must find out what is behind this changed Josie, and begin to come to terms with what is really at work on the planet.