Sep 18, 2014 Updated: 1:45 PM
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
Martin and Louisa are at their wits' end due to their constantly wailing baby; Aunt Ruth deals with an intruder on the farm; Martin treats a woman who believes her son is poisoning her.
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