Giles Woodforde goes behind the scenes at the Oxford School of Drama

It doesn’t immediately strike you as a powerhouse, but that’s what it is.

The Oxford School of Drama (OSD) sits in an idyllic rural setting just outside Woodstock, its Cotswold stone rehearsal studios blending seamlessly into the surrounding countryside. When I visit, small groups of students are sitting on the grass outdoors running quietly through their lines, while small birds forage alongside them, completely unfazed.

But the rural Oxfordshire calm is deceptive: recent OSD graduates have gone on to win leading roles in the BBC’s Wolf Hall and The Musketeers, on stage in the RSC’s Oppenheimer at Stratford, and in the feature film Kingsman: The Secret Service.

Last year, OSD student Samantha Colley was released from her course early. She had been picked to co-star with Hobbit heartthrob Richard Armitage in The Crucible at the Old Vic – the production was relayed to cinemas across the country.

“The emerging talent is what keeps one going,” says OSD’s founder and principal, George Peck. “The students come here with ambition: they want to act, and we test that ambition on a daily basis. At the end of their courses they manage to realise something that is really very special to them, and is profoundly important to their careers as creative artists.

“So I’m delighted when Claire Foy, for example, becomes a big star in Wolf Hall. But actually it’s the process she went through to get to that point that’s vital, and it’s the same with every student here. They start with something that is quite fragile, and build on it until it is robust – something that you can call professional. That process is very exciting – it’s wonderful.”

George Peck is a man for whom the expression “irrepressibly enthusiastic” might have been invented. He founded the school 27 years ago “in a derelict cottage just outside Oxford” with just nine students. Described by Nicholas Hytner, until recently director of the National Theatre, as “in the top rank of British drama schools”, OSD now accepts only four per cent of the candidates who audition for its one and three-year courses.

“We have a boy, Abram Rooney, who left two years ago,” George tells me with evident pride. “He’s now playing the lead in The Curious Incident of the Dog in the Night-Time in the West End. He holds that show together. There’s a lot of physical theatre involved, and also many of the other skills that we teach here. I think all our staff would agree: it’s not so much the stardom, it’s the thrill of seeing our students achieve their goals in the highly competitive world of professional theatre.”

Of course, no embryo actor is going to succeed if they haven’t made the vital transition from studio rehearsals to interaction with audiences paying hard cash. That’s why two contrasting productions featuring current OSD students are being brought into Oxford – John Gay’s The Beggar’s Opera will be performed in Oxford Castle Yard, while Shakespeare’s Julius Caesar will be on stage at the North Wall. Both offer chances to spot possible future stars, and both are in intensive rehearsal the day I visit the OSD campus.

“Having an outsider in our rehearsal makes me wonder: can he hear your consonants?” Louise Shephard, director of The Beggar’s Opera, tells her cast. “I suspect that he can’t,” she adds, reading my thoughts precisely. Louise promises to take Gay’s underworld story of treason and revenge “by the scruff of the neck”. Judging by the snippet I saw, there’s plenty of humour too – Jonathan Laird’s new musical arrangements feature a wicked take-off of Strictly.

Meanwhile, in an adjoining studio director Paul Hart is taking a fresh look at Julius Caesar.

“The more we’ve all collaborated in the rehearsals, the more we’ve found it interesting to enhance the importance of the female characters,” he says. “So I’ve gone for the idea that as the play develops, you get a sense of the new world order – the feeling of women taking over: Mrs Thatcher and Mrs Merkel if you like. It’ll be very interesting to see how it plays out.”

The Beggar’s Opera. Oxford Castle, June 3-6 Julius Caesar, North Wall Arts Centre, June 10-13.