Cosmic Arts' set occupied the North end of St Mary Magdalen Church, an awkward space here transformed into a Western Front dugout near St. Quentin in 1918. This makeshift, underground officers' billet, cleverly designed by Olivia Williams and associates, is lit by candles guttering among whisky and French wine bottles on a table, and furnished by two pallet beds with tartan rug; all under a tarpaulin roof. The sole lighting to back up the candles comes from a further row of candles on the floor at front stage. The play runs almost without music or sound until two late irruptions of guns, machine and artillery. Script and actors' voices are low-key and action is sparse. No fire-steps here, no shell holes, no whizz-bangs, no snipers. Unpromising material, one might think, and a big challenge for director Agnes Pethers and her colleagues, particularly given that they made the bold choice to run it without an interval.

Yet the audience on Saturday night for 2 hrs 15 mins sat rapt. You could have heard a pin drop in the church all through the claustrophobia and unbearable strain these men were experiencing, the dugout acting as a microcosm through which to explore the wider context of war. Hardy (a very good Dom McGann), the first officer we see, sits at table, his already jittery voice tending towards hysteria, his laugh a series of hiccups dwindling into a mirthless grin.

But subsequently RC Sheriff employs the flattening device of his officers spending much of their time in repeated discussion of, say, the cutlets that appear day after day on the menu, and of cricket and 'rugger'. How can they be fussing about the porridge, one wonders, with murderous raids into No Man's Land in the offing? In this way, though, the inadequacy of speech as a medium to convey the horror of war is suggested, and in any case the second meal we see is conducted in a febrile atmosphere.

Sheriff takes care to differentiate his characters, and any tendency to gloom is leavened by the itinerant presence of the cook/waiter (a very good Alex Marks, his humour unforced). The Company Captain Stanhope (Albert McIntosh) is the most complex of them, and McIntosh captures his mixed feelings towards Raleigh, his young schoolfellow, his assumption of the guise of the martinet, and his proximity to a crack-up as he repeatedly sloshes whisky into a mug. The actor's occasional clotted diction and lack of volume were small flaws, but he brought off marvellously well Stanhope's nightmarish visions inspired by his loneliness in command, leading to a dislocation from humanity as a whole.

Joe Stanton plays schoolmaster Lt Osborne with great finesse. He's the glue who holds these shattered comrades together, reader of fantastical passages from Alice in Wonderland and the narrator of a key anecdote of humanity exercised by a German. Stanton acted beautifully with his eyes – very few student actors can do that – and he makes of his departure to lead a 'forlorn hope' raid an emotional highlight, fear hanging in the air like the phosgene gas he has casually referred to, as he chooses to leave his wedding ring behind on the mess table.

Flinn Andreae makes a convincing Hibbert, on the verge of a breakdown after three months at the Front and determined to report sick despite his Captain's: 'Cheer-oh, and long live the men who go home with neuralgia!' followed by: 'You can stay here and try to be a man!'. I was unsure about Charlie Wellings' Colonel since his effete manner, I thought, tended to obscure rather than illuminate the extent of concern he felt for his individual subordinates. But as tyro 2nd Lt. Raleigh, Joe Woodman was plausibly fresh-faced and keen as mustard. Louis Cunningham was excellent as Trotter, a slightly dishevelled grammar school officer in a billet of public school men, his feet on the ground, drawing strength from his horizons being a little nearer than those of his colleagues.

Agnes Pethers' skilled direction generated energy from a group of stressed men sitting round a table; where the possibilities for movement were at a premium. The pace was relentless but somehow unhurried. The choice of holding back the sound of gunfire to near the end was inspired, and there were several little moments of director/actor collaboration where I held my breath – the violent confrontation between Stanhope and Hibbert over cowardice, the revelation of Stanhope's tactical plan to corral his Company in a tangle of barbed wire, metaphorically isolating and insulating them from the wider conflict; and a moment near the end where Stanhope sits slumped, a cigarette dangling from his trembling hand.

At the end, Pethers' invention was not quite exhausted even yet, since in place of a curtain call our 10 brave lads lined up and intoned the names of the dead from Oxford colleges in the Great War. A fitting end, though had there been a curtain call I would not have sat and clapped, but stood up and cheered.