There’s just three years’ difference in age between Captain Stanhope and Raleigh. But what a difference those three years make. Stanhope, at 21, is a whisky-soaked veteran officer, while Raleigh is an 18-year-old newcomer, who sees the army as a “simply topping” extension to life at his posh public school. In R C Sherriff’s classic First World War drama Journey’s End, Raleigh has been posted to serve under Stanhope’s command, and reports for duty at HQ, just 60 yards from the German front line.

In one of the many scenes that fizzle with tension in this new Watermill production, Stanhope is far from pleased when he first sees his new young officer, for they have met before: Stanhope was a prefect at Raleigh’s school, and an object of hero worship. The two families know each other. What if Raleigh (James Mack) describes his superior’s drinking habits in the letters he sends home?

But as director Paul Hart and actor William Postlethwaite — in a superb performance — make plain, Stanhope is a multi-layered character, not just another upper-crust drunk. “You’re a bloody funk!” he roars at Hibbert (Edward Killingback), who is openly terrified and requests referral to a doctor. Each downs a whisky, and Stanhope then confesses that he, too, is scarred stiff. They agree to go forward into the trench together. Later, Stanhope is horrified when he is ordered to send men forward on a suicidal reconnaissance expedition. His level-headed second in command (Jim Creighton, in an expertly understated performance) is killed. Stanhope is devastated.

Thanks, not least, to the work done by Princes William and Harry, there is increasing awareness of the damage done to young people who fight for their country, and survive.

As a result, Journey’s End doesn't seem to have dated at all — especially in a production that’s as well judged and staged as this one.

Journey’s End
Watermill Theatre, Newbury
Until October 11
Tickets: 01635 46044 www.watermill.org.uk