4/5. Dylan Winter investigates a former secret nuclear bunker in Essex, one of Britain's Cold War Regional Government HQs. Here, in the event of a nuclear strike, civil servants in 12 "regional seats of government" would have taken over the running of Britain. He tours it in the company of an anti-nuclear activist who tried to break in during the 1980s, and one of the officials who commissioned the bunker.
Producer Jolyon Jenkins