In the event of a nuclear attack "we would survive if we knew which areas were safe from nuclear fallout." ROC volunteers, trained to monitor bomb bursts and nuclear fallout, are shown in an underground headquarters. "But more volunteers are needed. A few hours a month... but you could help to save millions of lives." End title gives an address: "HQ Royal Observer Corps, Bentley Priory, Stanmore, Middlesex HA7 3HH".