The situation at the foster home continues to deteriorate, as Andy tries to help his foster daughter, Grace (Amélie Eve, "When Calls The Heart") overcome her agoraphobia. Meanwhile, Marcus and Tomas travel to Seattle where they encounter a new possession case, discovering a young girl who has been targeted by a force of pure evil. Father Bennett tracks down a rogue church operative named Mouse (Zuleikha Robinson, "Still Star-Crossed," "The Following") who is waging a one-woman crusade against the demonic conspiracy.