It’s not every day you get to hear a former Trotskyite squatter saying, “I once shared this room with Philip Glass and Doris Lessing”. Then again, it’s not every day a former Trotskyite squatter finds herself in charge of a major contemporary opera at London’s Coliseum.

“Yes,” laughs Penny Woolcock, director of Doctor Atomic, John Adams’s 2005 study of the Los Alamos ‘Trinity’ test explosion. “When the opera opened at The Met in New York, lots of my friends from that time came, because they just couldn’t quite believe the transition!”

“It all started in Oxford, really,” where Woolcock lived from 1972 to 1985 “in a kind of commune”, and then squatted in “a rather big house” on Observatory Street before “going legit” on Walton Well Road.

“Most of the time I did very, very menial jobs. I worked at the Radcliffe Infirmary, washing up. And I was a union rep. I painted, and I always wrote. But I couldn’t figure out how to make money from either of those things.

“So I sort of fell into youth work. It was an exciting and very volatile time: punks and skinheads and glue-sniffing down by Bonn Square. I’d been slightly delinquent myself, so I wasn’t afraid of them. I did a bit of drama with a group of young women, and then they said, ‘so what do we do now?’. And I said, ‘well, we’ll make a film, for Channel 4’, not realising that you’re supposed to have a commission, or at least know what you’re doing.

“And while making this short film — this was in about 1986 — I just knew this was what I’d been born to do. It brought all the things I was interested in together: the visual side, obviously, and writing, working with people, being able to create something adventurous out of nothing.”

Woolcock ‘fell into’ opera in much the same way.

“I’ve been a big admirer of John Adams since I encountered Nixon in China, his first opera. I’d moved from Oxford to Newcastle and went into a record shop, and they were playing something that sounded so fantastic I ran up to the counter and bought it, never thinking for a second that I’d one day be working with the composer.”

A few years later, she attended a concert performance of Adams’s second opera, The Death of Klinghoffer, about the hijacking of the Achille Lauro. She suggested to Channel 4 that she might film that too — and, confident that she wouldn’t simply point six cameras at the stage, they went for the idea.

Though she hadn’t met the composer, he’d seen her drugs-and-housing-estates film of Macbeth.

“I hope you’ll be as radical with my opera as you were with Shakespeare,” Adams told her. They cast it together — to assure both realistic performance and decent singing (radical, radical!) — and she promptly set about drilling her ‘Palestinian’ terrorists in how to strip a Kalashnikov in 30 seconds. With award-winning results.

So when Doctor Atomic came up, Adams immediately nominated Woolcock. “So, out of the blue, having never directed for the stage before. It’s been an incredible experience.”

“There are a lot of differences,” she points out, between film-making and stage. No emotive close-ups. No cutting from one location to another.

“You have to be much more inventive. Naturalism doesn’t really work on stage — the stage is not the desert! And opera is not naturalistic: it’s a quite deliriously insane art-form.”

And yet here is this art-form, dealing with the mother of all non-fictions: the decision to drop the world’s first atom bomb.

“The opera doesn’t tell you what to think (that would be preachy and boring); but it does question whether dropping the bomb was necessary. John and I have different views, in fact. I feel these men wiped out a quarter of a million people in 30 seconds and people talk about how clever they are; but if a kid from Blackbird Leys goes into town and stabs one person he’s seen as subhuman. It’s a terrible double-standard. There’s a way of looking at it where Hiroshima is really a horrendous war crime.”

“But John is still torn. He thinks that under the circumstances he would have supported Oppenheimer.”

Few composers could set “A sustained neutron chain reaction/resulting from nuclear fission/has been demonstrated” (in the opening chorus, no less) alongside poetry from the Bhagavad Gita and get away with it.

“A lot of people think of contemporary music as being very dissonant and difficult to listen to. But John’s music isn’t like that. It’s very beautiful and accessible.”

It is a rare concern that a contemporary opera might actually beautify a morally horrifying event, but Adams is a special case.

Could audiences find themselves inappropriately seduced by his lyricism?

“There’s always a stunned silence at the end.”