On 6 June 1944 when the allied armies landed on D-Day, the Second World War had already lasted almost five years.

Yet many of the British and American troops who invaded Normandy were virgin soldiers, never before committed to battle. They quit summer England to face within hours a storm of machine-gun and mortar fire. They witnessed scenes, above all of sudden death, such as no exercise had prepared them for.

In Sword, veteran chronicler of war Max Hastings explores with extraordinary vividness the actions of the Commando brigade, Montgomery’s 3rd Infantry and 6th Airborne divisions on and around a single British beach. He describes their frustrations, hopes, loves and fears through the apparently interminable years training and preparing in England, then their triumphs and tragedies on the beach and beyond. Here are the airborne assaults on the Caen Canal bridge and Merville Battery, the battles on the shoreline and against the German strongpoints inland, narrated and explained with all the insights that Hastings’ decades of study, veterans’ interviews and new archive research enable him to deploy.

The book offers a searching analysis of why British troops did not reach Caen on 6 June, as Montgomery had promised Churchill that they would – and the story of the brigadier who was sacked for that failure. There is also a host of personal portraits of key figures from commando leader Lord Lovat, famously brave but supremely arrogant, to tank colonel Jim Eadie, whose tanks of the Staffordshire Yeomanry repulsed a panzer division in the last hours of 6 June, and some of the humbler participants to whom extraordinary things happened.

This is D-Day as you have never read the story told before, with the blend of narrative, analysis and human insight that made Max Hastings’ last book Operation Biting, like many of his earlier works, a Sunday Times No.1 bestseller.