The World at War is one of the most ambitious documentary series ever made. A mammoth 26 hours charting key points in the history of World War Two.
Over the past few decades it has inspired countless TV and film makers, including Oliver Stone; his own recent series The Untold History of the United States was inspired by the groundbreaking show.
October 31, 2013 marked the 40th anniversary since that first broadcast of The World at War, and Sir Jeremy Isaacs, who conceived and produced the series, reflects on the Bafta and Emmy-winning documentary.
Getting a project like that off the ground was no easy task, so how did it come about?
"It came around because it's a great subject, a great subject that was waiting to be made into a television documentary series," explains the eloquent eightysomething.
"As soon as the BBC did a series on the First World War, The Great War, really it was then just a question of when and who would do the Second World War."
Isaacs was a key force in fact-based programming in the late 1960s. He'd earned his stripes as a current affairs journalist, and was also responsible for documentaries at Thames Television.
He had previously worked at the BBC editing Panorama, but a disagreement led to him moving on... until he was made an offer by the Beeb - the seed of what would become The World At War.
"To my amazement, someone at the BBC asked me if I would like to produce a history of the Second World War," he recalls. "I said, 'Well I've got a good job here, but I would be very interested'. And then I discovered that they asked all sorts of other people."
However, the BBC's war project stalled. The powers-that-be didn't want to make a major commitment towards such an expensive series using so much black and white footage. (This was at the time when colour TV was becoming mainstream).
By that point, Jeremy was fascinated by the idea of making a series about the Second World War, though he wasn't keen on making a show just about 'The combat of the war'.
"I wanted to do a series about the experience of the war; the home front during the war; the war economy of the five great combatant nations and so on and so forth. I wanted a little leeway (with the show) not to have to depend every week on bombs and guns and tanks and so on."
Of course, if the BBC wasn't keen, he thought of a company that might pick up the baton.
"I remember thinking, 'Well if the BBC doesn't want to do it why don't we do it (at Thames)?'"
Getting a green light for a 26-part series on commercial TV was no easy task either, as Isaacs recalls.
"Well, it (Thames) was the biggest and perhaps most successful band of the ITV company we were part of a network. Getting space for an extra three documentaries a year was a big negotiating deal. Getting space for 26 documentaries was going to be tough!"
Help came in February 1971 from a change in the law which gave ITV more money to spend on programmes.
To cut a long story short, Isaacs got a green light, and then the really hard work began.
For three years a team of 50 researchers, editors, Imperial War Museum experts, and assorted other programme-makers toiled over what would become a TV milestone.
Ask many original fans of the series what they remember, and aside from Carl Davis's suitably imposing score, there's a chance Sir Laurence Olivier's narration would be a key element.
However, at one point early in the production it looked like Sir Jeremy might have to do the unthinkable and sack the acclaimed thespian, who wasn't his first choice for narrator.
"I didn't want to have an actor reading somebody else's words," he explains. "The documentaries I made were made by reporters who wrote and read their own narratives, and there were some pretty good guys around I had worked with and could have helped to do that."
One of them was Ludovic Kennedy, but with ITV devoting such a large chunk of time and money to the series, they wanted a more bankable star for The World At War.
"They were providing the platform for it. They felt, and the sales department felt that we needed Olivier, because Michael Redgrave had done a marvellous job with the BBC on The Great War, and they wanted somebody at least as good if not better to do the narration."
Alas, the initial voice-over on that inaugural World At War show was far from successful.
"The first programme we recorded on The Fall of France," explains Isaacs. "Larry was... I never called him 'Larry' by the way. I probably called him 'Sir Laurence'. He was very tired; he did it very badly."
A colleague told him the recording was no good and Olivier's voice kept 'falling off at the end of every line'.
He suggested to Jeremy, "You'll have to let him go".
The thought of having to sack one of the world's greatest actors left Isaacs shaken.
"The idea that I might have to tell Laurence Olivier that he was fired was a bit much for me to take on".
"I had a fairly sleepless night until he turned up again the next day to record of the next episode."
Isaacs played Olivier the first episode he'd recorded, and the thespian realised fatigue had got the better of him. Given his workload up to that point there was little wonder.
"After 20 minutes he said, 'Of course there is something wrong. I seem to have been tired and you must excuse me, I'll do it again'.
"He had been making a film called Sleuth, which went on a lot longer than he thought it would, and he had done 21 performances of Eugene O'Neill's play Long Day's Journey Into Night in the weeks immediately preceding these recordings, so he was whacked."
Olivier focused his attention and Isaacs noticed a vast improvement in the narration.
"There after, whether he'd studied the script or not before he arrived in this little recording studio in Oxford Street - they would sometimes show him the film before he recorded it, and sometimes we went straight in - he was superbly professional and did it marvellously well. I have always admired him for it and been grateful to him for it."
Okay, not everyone loved the narration.
"Some people still think that his voice was too mannered," explains Sir Jeremy. "I don't think that the public who adore the series would agree with that."
Thanks to a 2010 digitally remastered version, The World at War now looks and sounds better than ever.
It may have been one of the most expensive British shows ever made, but because of the wealth of interviews, rare footage, and stunning research, it's also one of the most important shows ever made.
In another four decades from now, I doubt many would disagree.
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