Sam Hunter returns to work one year after narrowly surviving an attempt on her life.
Sam and the team continue their surveillance of Jack Turner's secret activities.
Sam thinks a man from her past may have something to do with the attempt on her life.
Turner hatches a diabolical plan; Aidan uncovers some of Sam's secrets.
Sam awakes in the hospital and finds a familiar face who promises to be an ally.
Sam and Stephen grow closer; Sam continues her investigations into Hourglass.
Sam makes a startling revelation; Aidan tells Natalie to uncover the leak in M16.
Byzantium fails to kill Jack Turner; Sam is exposed to a spy.