Jul 31, 2014 Updated: 11:34 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
Martin meets the midwife who'll be caring for Louisa and has a run-in with her over her use of herbal remedies. He also overcomes his blood phobia and decides to become a surgeon in London again.
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