Apr 18, 2014 Updated: 12:40 AM
A modern, edgy drama full to the brim with passion, politics and peril. MI-5 leads us into the dangerous world of Britain's top-secret security agency, and into the lives of people who must lie, and sometimes die, for a living.
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Harry instructs the team to investigate a possible Russian link to Adam's death, but orders Lucas to remain on the bench over doubts about his loyalty.
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