Out on the Western Front a cast of five actors are keeping their heads down in “Yorkshire Trench”, a preserved portion of the British line near the city of Ypres, known to every Tommy as Wipers. The performers are on a recce. They are soon to be acting a stage version of The Forgotten Voices of the Great War, the best-seller that trumps all other what-it-was-really-like war books.

The trench is neatly sandbagged but with not a rat or a Boche in sight. The towering Matthew Kelly (the Stars In Their Eyeshost, more recently reinvented as a stage actor) plays a cheery private in the forthcoming show. But when it is explained that he would have been crawling with lice, suffering from the runs, and under threat of execution should he fall asleep on sentry duty, he pipes up: “I’m not sure I like this war.” Few did. The book consists of 200 or so verbatim accounts of the war from recordings made in the 1970s by the Imperial War Museum as part of their ongoing oral archive. In 2002 the author Max Arthur painstakingly turned these into a book which has so far sold more than 500,000 copies. The testimonies from these survivors register just about every emotion, mood and ordeal that the men “over there” and the women left at home went through, year by year, from 1914 to 1918.

Apart from Private Kelly, also on the trip is the glamorous Belinda Lang who will play a munitions worker, Steven Crossley (an American soldier), Rupert Frazer (a British officer), and Tim Woodward (a sergeant). The adapter-director of the piece, Malcolm McKay, is also on the bus and Max Arthur brings up the rear with supplies of peppermints, jokes and expertise. We form a right Karno’s army (as they used to say) as we wend our way around the melancholy battlefields of the Ypres and Somme sectors.

Our genial guide is Julian Whippy, a former police sniper, whose company is Battle Honours Ltd. There is just nothing this chap doesn’t know about the Western Front and the strange khaki world of the pals who fought on it. He explained how “chatting” is an Indian army word; the difference between a parapet and a parados; how trench life was 99 per cent boring routine. It was the unhappy lot of the PBI (poor bloody infantry) to do nothing and be shelled. He also told us about going over the top. Rupert Frazer chuckled at this: “Darling, that’s the one thing we actors know about.”

But for the most part our tour was horribly sobering. At Ypres we went through the Menin Gate, the memorial dedicated to some of the men with no known grave who were killed in the Ypres Salient.

Out through Ypres passed the best part of a million men into the “immortal salient”. Some 250,000 never came back. The Menin Gate Memorial, massive though it is, wasn’t large enough. “Brace yourself” was Max Arthur’s wise advice to me as we got off the bus a few miles later. Tyne Cot Cemetery is an overwhelming experience. It takes a lot to shut actors up; this place did it instantly. Here was the Third Battle of Ypres, known as Passchendaele, a terrible “show” that was fought with epic losses on both sides. The green slope today was, in 1917, an obscene porridge of mud, with corpses, gas, endless shells and incessant rain. The German pill-boxes are preserved intact within the cemetery where today 12,000 lads lie shoulder to shoulder in serried ranks facing the fatal ridge as if on horizontal parade. The place is numbing.

For sheer impact it perhaps beats even Edwin Lutyens’s vast 1932 memorial to the missing of the Somme at Thiepval, its huge arches containing seemingly endless columns of some 73,000 names. Today it’s a sacred spot. What the visitors’ centre doesn’t tell you is that when it went up many war veterans regarded it as a waste of money which would have been better spent on decent pensions.

To modern historians, the play Oh What a Lovely War! has a lot to answer for in converting the postSixties generation to the now widely contested “lions led by donkeys” theory of the war. “But those headlong assaults were completely bloody mad!” protested Tim Woodward over supper at a restaurant in Albert, attempting, like the rest of us, to comprehend a war in which brutal attrition was the name of the game. Tim’s father is the actor Edward Woodward and his grandfather, a champion boxer, fought with the East Surreys, though he wasn’t sure of the details. The next day, Matthew Kelly located his maternal granduncle’s grave in a small cemetery and put a poppy and cross in front of the stone.

Out on the Somme, at Serre, none of us could quite visualise this green, undulating land on July 1, 1916, thick as it was with British dead along a 12-mile front: the worst day in British military history. A more digestible spot was the Beaumont Hamel Newfoundland Memorial, dedicated to the Newfoundland Regiment, a ferociously loyal bunch of beaver-trappers and fishermen whose first battalion suffered 90 per cent casualties on that sunny morning. A splendid bronze caribou perched on a mound now faces the German lines. Malcolm McKay as adapter of the book explained that, while being no war expert, he was a huge admirer of the voices – the survivors – captured verbatim in the book. “It’s very beautiful stuff about the endurance of the spirit in terrible times. It’s very moving – and what’s moving about it is the courage. The difficulty is finding a way to stage such wonderful material.”

In the bus on the way back to Blighty battle fatigue had set in on our little unit of footsore pals. To lighten the mood Blackadder Goes Forth was shoved on the overhead DVD player. We smiled when Stephen Fry’s General Melchett said, “I wouldn’t lick a German if he was glazed in honey”, but somehow the laughter didn’t come. The cemeteries of the Western Front cast a very long shadow. Forgotten Voices should – with luck – be an act of commemoration while also summoning up the Western Front’s eerily potent spell.

Forgotten Voices, Riverside Studios, London W6 (www.riversidestudios. co.uk 020-8237 1111), May 30–July 7

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