Oct 31, 2014 Updated: 7:43 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
Dr Martin Ellingham arrives in a Cornish hamlet to take over the local doctor's office, but the residents are wary of the flashy newcomer.
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