Television: Testament of longevity

Even the sound engineer was moved. Peter, a dour Scotsman, had been caught labelling the insert of a 1937 recording of Vera Brittain's voice which opens Letters From a Lost Generation with the words "posh old cow". Yet, after sitting through the recording of 15 episodes of this adaptation of her First World War letters, he was visibly affected. "There won't be a dry eye in the house," he promised. "Did all this really happen?"

The answer, of course, is that it did. For almost 70 years now, the story of Vera Brittain's experiences in the First World War during which she served as a VAD nurse and lost the four men who meant the most to her - her fiance, Roland Leighton, brother Edward, and her two closest friends, Victor Richardson and Geoffrey Thurlow, all killed in the war - has held readers enthralled.

"If the War spares me," Brittain wrote to her brother Edward in 1916, "it will be my one aim to immortalise in a book the story of us four." Seventeen years later, Vera Brittain published Testament of Youth, her autobiographical study of the years 1900 to 1925. It became a bestseller on both sides of the Atlantic and made her famous. As Winifred Holtby noted in a description that remains as true today as it was in 1933 when she wrote it, "Others have borne witness to the wastage, the pity and the heroism of modern war; none has yet so convincingly conveyed its grief."

In the late Seventies the book became a bestseller all over again when it was republished by Virago Press. Carmen Callil, the famously no-nonsense head of the company, had wept while reading it, and had resolved to see it in print again. A much lauded BBC television dramatisation starring Cheryl Campbell followed in 1979, which swept up most of the major Bafta awards. By that time, Testament of Youth was firmly enshrined as part of the canon of First World War literature and has remained so ever since.

Letters From a Lost Generation comprises the letters, written from 1913 and 1918, between Vera Brittain and the four young men who were part of that doomed generation who went almost straight from school to the dreadful fate that awaited them on the battlefields of France, Belgium and Italy. This correspondence, which survives today in the Brittain Archive at McMaster University in Hamilton, Ontario, formed the backbone of Testament of Youth. Vera Brittain quoted from some of them, convinced that nothing she could write would bring her major protagonists so vividly alive as their own words. But even so, only a small proportion of the 560 or so existing letters have been published before: Brittain was prevented by the restrictions of copyright from printing some, while others, for instance those written by Geoffrey Thurlow to Edward Brittain, were embargoed for a decade after Vera Brittain's death in 1970 because of the fear that they might reveal something unpalatable about Edward's alleged homosexuality. (In the event, they neither prove nor disprove the allegations.)

These letters are in many ways unique. Few collections of First World War letters span the duration of the conflict, or present both sides of the correspondence. Fewer still offer both male and female perspectives. Furthermore, the broader picture which it provides allows us to see and understand the war from several points of view: that of the young officer in the trenches, of the volunteer nurse in military hospitals at home and abroad, as well as glimpses of what the war was like for civilians on the home front.

The letters themselves give the new radio series an extraordinary and powerful immediacy, but for the 15 14-minute Woman's Hour slots it was necessary for me as adaptor to reduce the published version of the letters by as much as three-quarters while still attempting to preserve a strong and suspenseful narrative line.

The producer, Clive Brill, had assembled a strong cast, including Amanda Root as Vera, Rupert Graves as Roland and Jonathan Firth as Edward. After extracting information about Roland's background, Rupert Graves assumed the cultured voice of a brilliant, prize-winning poet, the first of the schoolfriends to die, in December 1915 in France. Amanda Root's plangent tones served to emphasise the encroaching tragedy, while Jonathan Firth imitated Edward's charm and easygoing manner, the perfect foil to his sister's more intense and confrontational personality. The atmosphere was heightened by the use of original recordings of First World War songs - Roses of Picardy, Your King and Your Country Want You, and Good Bye- ee - as well as, in more sombre moments, Elgar's setting of Laurence Binyon's poem "For the Fallen".

Taken together, the correspondence presents a remarkable portrait of five young people caught up in the cataclysm of war, writing and responding to one another's reactions and to the tumultuous events as they occurred; and while, by their very nature, the letters are often tragic and doom laden, they also celebrate the enduring importance of friendship and loyalty between Vera and the four men, and among the men themselves.

As John Keegan has recently observed, this was a war that elevated the loyalties of peacetime and strengthened the ties of the closest brotherhood, and one need look no further for illustration of this than the relationships "unto death" of the three friends educated at Uppingham School: Roland, Edward and Victor.

But the letters remind us also of the other kinds of ties that bound these men in proud service to their country: the values of honour, duty, patriotism, self-sacrifice and "heroism in the abstract". "I feel ... that I am meant to take some active part in this war," Roland wrote to Vera before leaving for the front. "It is to me a very fascinating thing - something, if often horrible, yet very ennobling and very beautiful." Even after inevitable disillusionment has occurred, the voices of these schoolboy soldiers remain remarkably unresentful and unquestioning of their fate.

At the end of the final episode, above the shouts of the crowds which marked the first Armistice Day, we hear the voice of Vera Brittain, the only survivor of her intimate circle, cast suddenly into a harsh post- war world. She announces the beginning of a new age in which she will go on to pick up the pieces of her life, enjoy marriage and motherhood, and take up the banner of feminism and pacifism.

'Letters From a Lost Generation' begins 19 October, 10.45am, on Radio 4.

'Letters From a Lost Generation: The First World War Letters of Vera Brittain and Four Friends' edited by Alan Bishop and Mark Bostridge is published by Little, Brown on 5 November.