When the Royal Shakespeare Company (RSC) asked Tom Morton-Smith what he wanted to write he pitched an eight play sequence about physics in the 20th Century.
The RSC got him down to writing a single piece about J Robert Oppenheimer, often described as the father of the nuclear bomb. But it remains ambitious: the play has to teach its audience a lot about radical politics in 1930s America and about the race during World War Two to harness nuclear fusion.
The science in Morton-Smith's new work for the RSC is concerned with the smallest things - protons and neutrons.
So it's ironic that Oppenheimer, now playing in Stratford-upon-Avon, originated in a scheme to make authors think big.
"About three years ago the RSC had invited a bunch of writers to see if we could benefit from the sort of facility they use routinely with actors," the playwright says.
"Things like vocal coaches and advisers on rhetoric. They made me get up on stage and do Greek choruses and work on a couple of Shakespearean soliloquies.
"The idea was to get us thinking more epically and on a level suitable for a big stage like the Royal Shakespeare Theatre in Stratford or the Swan next door. They wanted to get us beyond small plays with conversational dialogue."
After a couple of weekends building theatrical muscle in Warwickshire, Morton-Smith got to pitch ideas to the RSC Literary Department. "I pitched eight plays telling the whole history of physics in the last century. They laughed and said, 'okay, let's select the idea you're most interested in'. And that was J Robert Oppenheimer."
Oppenheimer was born into a prosperous family in New York in 1904. After Harvard, he studied at Cambridge and then at the University of Gottingen in Germany. He came to focus his intellect on quantum mechanics - the science of the smallest things.
In 1942 Oppenheimer was appointed to run part of the Manhattan Project, the ultra-secret US programme to develop nuclear weapons. The laboratory he supervised at Los Alamos in New Mexico had the task of making the complex physics work before the Germans did.
In fact after the war it became clear that German capabilities had been much less advanced than the Allies thought. The lead which Germany had enjoyed in particle physics before World War Two had been wasted because research was splintered between too many competing institutions.
The notion that any one person was "father of the bomb" is simplistic but Oppenheimer was certainly central to advancing the Allied research effort.
Morton-Smith says it took him a year to come up with a draft of the new play.
"The RSC gave me what they call a seed commission - a small amount of money to let me research the idea. In this case that meant reading an awful lot of books and watching documentaries.
"So much of what happened in the rest of the 20th Century - and is happening today - seems to lead from the work Oppenheimer and his colleagues did. It's a big story, which is exactly what the RSC wanted."
Morton-Smith thought hard about how much scientific detail he should include.
"I had to write for people who understand a proton or an electron far better than I ever will - but also the play's for audiences who would find too much science a total turn-off. Plus you can't tell this story without including background detail about left-wing politics in the 1930s and 40s.
"But I don't go beyond the war so I didn't have to go into what happened in the 1950s: that would be another play." (In 1953, in an era of virulent red-baiting, Oppenheimer had his security clearance withdrawn for alleged past sympathies with the Communist cause.)
"In the first few scenes of the play we see everyone collecting dollars for Soviet Russia. Some people will think the scientists were a bit naive but they didn't know everything that was going to happen under Stalin. There was some wide-eyed idealism.
"By the same token people didn't know what the long-term effects would be of radiation. One of the hardest things was to try to think myself into the mind-set of scientists who knew what they were doing would probably lead to dropping the bomb on Japan.
"In the moment they felt they were doing the right thing. Of course what they felt afterwards was different for some of them."
So did Morton-Smith end up sympathetic to Oppenheimer? "Pretty much everyone involved with the Manhattan Project eventually wrote an autobiography and there are so many magazine pieces too. You get a slightly different Oppenheimer in each of them.
"It's obvious he was a very charismatic guy and generated a lot of respect. But that's not the same as being personable or likeable. He could be very difficult. I think the interesting journey for him was from idealism to cynicism.
"People always remember what Oppenheimer said went through his mind when he witnessed the first test explosion in New Mexico in July 1945 - 'I am become death, the destroyer of worlds'.
"That terrifying quotation is from the Hindu text, the Bhagavad Gita. But the journey for a man to reach that point felt quite Shakespearean to me, or even Faustian. It's quite enough for one play."
Oppenheimer died of throat cancer in 1967. So why does Morton-Smith want to revisit his story now?
"Nuclear issues still count in a big way. Look at what's being going on with Iran or North Korea, for instance. It would have been a big issue if Scotland had voted for independence.
"And there's quite a lot in the play about government surveillance, which is highly topical. And what morally we're prepared to do to fight a remorseless enemy."
By chance Morton-Smith reached the end of the writing process just as two high-profile films faced similar questions of how much science you can include in a story for a general audience which focuses on scientists.
How does he judge the scientific content of The Imitation Game and The Theory of Everything?
"Actually all the time I've been tying the script down I deliberately avoided seeing either film. I wanted to solve my own problems rather than see how other writers solve theirs. But probably now I'm free to see the movies."
Oppenheimer is running at the RSC in Stratford-upon-Avon until 7 March.