May 20, 2013 Updated: 7:30 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.
VISIT THE BBC's MI-5 WEB SITE
The team tries to get back an assassin's kit that's being sold online, but runs straight into an MI6 black op; Harry enlists the aid of a Russian sleeper agent in identifying the MI5 mole.
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