Nov 26, 2014 Updated: 11:24 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
Ruth attracts a mystery admirer when she appears on Radio Portwenn; Doc and Louisa find a replacement nanny; and one of Louisa's pupils reviews Bert's restaurant in the school magazine.
Find out about upcoming shows and events. Enter your email address below.