Peter Jackson. Photo / Getty
Peter Jackson is to tell the "true" story of the Dam Busters in a film remake, including details that were not included in the original because they were covered by the Official Secrets Act.
The 1955 version starring Michael Redgrave and Richard Todd told of the daring Second World War mission to destroy German dams with Barnes Wallis's 'bouncing' bombs.
But in an interview with The Telegraph Jackson said it presented a "romanticised" view and was short on detail because so much of the planning was kept out of the public domain.
Fresh from the success of his First World War documentary, They Shall Not Grow Old, the Oscar-winning director reaffirmed his plans for a remake. He has been trying to get the project off the ground for a decade.
"We are clinging on to the rights for The Dam Busters and we have them for another year or two," Jackson told the Telegraph.
"It's just a great story. It's always been a great story. But it's an even greater story now than it was in 1955 because back then there was still so much of the story that was under The Official Secrets Act.
"They couldn't show the bomb spinning because the fact that they applied backspin to the bomb to make it jump on the water was still a state secret.
"The film had a slightly romanticised view of what happened. It's reasonably accurate but the real story is so much more interesting. It's a story of politics, of ingenuity and peril, and it's also a story about trying to make a weapon to destroy these dams and that cost an awful lot of money.
"You see some of that in the original movie but there's a lot more of that that took place and that's as much of an interesting story as the actual raid itself."
Jackson has bought the rights to James Holland's best-seller, Dam Busters: The Race to Smash the Dams, which includes declassified information unavailable in the 1950s.
Holland is credited as a historical adviser on the project. He said: "All the actual science of it was kept secret in the 1950s. What they were actually dropping was a depth charge, not a bouncing bomb.
"The idea is that it bounces, hits the wall of the dam, rolls down until it sinks to a certain point, then there is a timing fuse so that by the time it has sunk it explodes. And at the moment of explosion it has the right amount of depth to create this weight of water pressure above it, which will exacerbate the explosion and do enough damage.
"In the film you see them flying low and it all looks like fun. But the whole process of getting deep into the heartland of Germany at night in a 102 foot wide, 30 ton machine with a four-ton rotating bomb underneath is almost impossible and [in the film] none of that comes through."
The portrayal of Wing Commander Guy Gibson, the hero who led the mission, was "anodyne", Holland said.
Gibson's struggle was not portrayed in the film, Holland said, because "in the 1950s you didn't go around talking about combat fatigue".
"He was clearly suffering from combat fatigue at the time of the dams raid and in a complete state. He should have been taken off flying. He had much less training time than anybody else because he was constantly having to go for meetings with Barnes Wallis and senior commanders.
"And yet he led the entire raid. If anyone deserved a Victoria Cross, it's him. I remember talking to Winkle Brown [Captain Eric Melrose Brown, the most decorated pilot in Royal Navy history] who said Guy Gibson told him that every time he got in a plane he was utterly terrified. And yet somehow he hid that from everybody else and found the courage to provide unbelievable leadership."
Holland said the 1955 film is "terrific" but contains many small inaccuracies. "Barnes Wallis is portrayed as this brilliant amateur fighting against a brick wall of desk wallahs, and it just wasn't like that. Some people were all for it and some were against it.
"That is really important and one of the brilliant things about the British in the Second World War - there were lots of enlightened people prepared to back crazy ideas in the interests of furthering the war effort."
He said of the real story: "At every turn the drama, the excitement, the machinations the two steps forward and one step back is better than the film and better than most people think."