With temperatures soaring to 35ºC, severe water shortages and a sunburned population queuing at the standpipes, the summer of 1976 was always remembered as Britain’s hottest.

But the wave that hit the UK that year was also cultural and political, with upheaval on the streets, in parliament, on the cricket pitch and on the radios and TV sets of a nation at a crossroads.

Before this blistering summer, Britain seemed stuck in the post-war era, a country where people were all in it together – as long as you were white, male and straight. In July, Tom Robinson writes a song called Glad to be Gay, and by August bank holiday, Black youth are making the police run for their lives in the almighty riot at the Notting Hill Carnival. But with the Labour Prime Minister Harold Wilson suddenly quitting, the pound sinking and the economy tanking, a restless immigrant population and increasing dissatisfaction in the old world order, the weather seemed to boil up the country to the point where the lid blows off.

Weaving a rich tapestry of the news stories of the year, with social commentary and dozens of first-person interviews with those that were there at the time, Williams’s reappraisal of the summer of ’76 is an evocative, sometimes nostalgic but always an unflinching read. Heatwave takes us back to relive the events of that summer and asks – have we really moved on as much as we would have liked?