Pressure is on as David shares war hero's story; D Day was a great risk and ultimately a success. David Haig tells DAVID WHETSTONE about the little known figure who can take much of the credit.
THINK of the heroes of the Second World War and you'll probably bring to mind military men or perhaps the brave agents - men and women - of the Special Operations Executive who went undercover to thwart Hitler.
A weather man might be low down your list, or most likely not feature at all.
But a play at the Theatre Royal this week puts meteorologist James Stagg centre stage. It is called Pressure and that isn't just an allusion to the weather.
Group Captain James Stagg was the man who advised General Eisenhower on the conditions likely to prevail on D Day when 350,000 troops were to invade occupied France in Operation Overlord.
Stagg is played by that fine actor David Haig who also wrote the play. Who better to put both play and character in context? "James Stagg was a dour, tenacious Scot but with a steely honesty which essentially saved Europe," says David.
"He persuaded Eisenhower to delay the D Day invasion because he saw appalling storms coming in on the 5th of June.
"Really he was ahead of his time as a meteorologist in understanding about the jet stream."
This is a climatic feature comprising ribbons of strong winds high above Earth's surface which can reach speeds of 200mph and affect sea and weather conditions.
For those planning Overlord, you can imagine the seriousness of any sort of delay, given the huge effort expended in massing all those men and their equipment in conditions of strict secrecy.
If word leaked across the Channel about what was in store, the Germans would have had a chance to strengthen their defences.
On the other hand, if the invasion foundered in a storm at sea, the upshot would have been unthinkable. When the invasion did take place on June 6, 1944, it was no picnic. Most of the soldiers suffered from seasickness but David Haig suggests Stagg saved about 80,000 lives.
He believes lesser man might have cracked under the pressure to please the top man, especially since another meteorologist, the American Irving P Krick, was offering different advice.
When Stagg forecast a dangerous storm, Krick, more used to the steadier American climate, predicted beautiful weather on the day chosen for the invasion.
"But then," says David, "having told Eisenhower to delay, Stagg had to go back to him to say he had spotted an eight-hour window when the invasion could take place. "You can see how it looked. When Stagg persuaded Eisenhower to postpone, there was bright sunshine. When he went back to persuade him to go, it was during one of the worst storms for 100 years."
Krick, said David, had based his predictions on past experience, saying "this is what happened in 1921 so it'll happen again tomorrow.
"He didn't understand what Stagg understood which was the changeability of British weather."
David says it was in 2013 that John Dove, director of Edinburgh's Royal Lyseum Theatre, rang to say he was looking to commission a Scottish story.
"He said he had a book about famous Scots and there was a chapter on James Stagg.
"I thought instantly, this is an extraordinary story that nobody knows about."
David says his play is not only about Stagg but about Eisenhower (played by Malcolm Sinclair) and Kay Summersby (Laura Rogers), the woman assigned to be the general's chauffeur but who later became his personal secretary and emotional crutch.
"For three years of the war she kept him stable and the relationship was allowed to continue," says David.
David Haig's first very successful play, My Boy Jack, is set in the First World War and focuses on Rudyard Kipling's grief at losing his son.
"People ask me do I always write about the war? Well I don't but these two seem to have been the ones that hit the bullseye.
"I think what fascinates me about it is the intensity of experience people go through in times of war, that sense of urgency and loss."
David, whose father and grandfather were in the Army, said he had been "slightly anxious" that people, especially young people, might not share his enthusiasm for the Stagg story.
"But we've had a wonderful response."
As for performing in his own play, David says: "It's bizarre because what I don't worry so much about is what I'm achieving as an actor.
"That doesn't mean to say I don't mind if I'm no good but I'm less bothered about creating specific moments for the actor. I'm more interested in portraying the man."
And that man, according to David, "was one of those remarkable Scots.
"I think he probably had a terseness to him that initially might have appeared rude.
"But when you got to know him you'd have realised he had this great integrity which is why people respected him enormously.
"There is something about him. He was one of those people who stick to their guns and don't allow themselves to be swayed by other people." Fortunately Eisenhower allowed himself to be swayed.
David says a film version of Pressure has been commissioned but he doesn't reckon on playing Stagg on screen. "At that point I bow to the greater stature of others."
Pressure is at Newcastle Theatre Royal from tomorrow until Saturday. Tickets: www.theatreroyal.co.uk or tel. 08448 112121.
David Haig as James Stagg in Pressure, also below