The Chilean Miners - 17 Days Buried Alive
The Chilean Miners - 17 Days Buried Alive was really conceived on day 18. The miners had just been found - though not actually rescued for another 52 days - and I was rung while on holiday by Guillermo Galdos, a colleague from Peru.
He descended on the mine and has made two very good films about the miners - one about the rescue and another about what happened next - but I was always fascinated by those first 17 days when no one knew if they were alive or dead.
And, most terrifyingly, the miners were half a mile underground not knowing if anyone would ever find them.
A universal nightmare we can all identify with, made worse by darkness, lack of food, heat and humidity.
Initially we thought we would never get the story because of a supposed secret pact taken by the miners not to talk about that period - and, of course, because of talk of million dollar Hollywood deals.
But quietly, and somewhat below the radar of big names, we established contact and trust with a number of the men and their families and worked out that it was possible to tell the story.
We took them one-by-one to a villa in the Chilean capital Santiago for "interrogation". Or more like therapy.
It was an intense and emotional experience for them - and us - as we took them back through the experience of those days - the fears and hopes.
It was clear - and I hope this comes over in the film - quite how deeply affected they all are by the experience.
They were workers who had gone through an extraordinary experience, and the power of the story they had to tell was, of course, made stronger by the fact they emerged as some of the most famous men on the planet.
Their simple emotional eloquence touched us all, and I hope we have captured that in the film.
Many have talked about the miracle of them getting out. They certainly, in their different ways, had spiritual experiences, from the ones who felt the devil with them, to those who found themselves blessed.
One talked of the tunnel as being his mother's womb (his mum had died giving birth to him) and that the rescue was a rebirth.
And, of course, the whole team wondered how they would have coped in such a situation, and laughed when one of the men said, "It's good that we were all workers. If there had been a professional they would have had their degree and their ego around - and egos kill."
We certainly all agreed that 33 filmmakers down a tunnel would not have survived!
The next stage for us was the reconstruction, which we did a couple of months later, down a nearby mine, high in the Atacama Desert. It is astonishingly beautiful, in a dry harsh way. We used other miners we hired in.
We decided to shoot the reconstruction on a very old film system, Super 8, which, for those of you under 30, was the older generation's way of doing home movies.
I was looking to create a sense that the material down the mine was real and caught that sense that these men had spent their time in another world.
It was tough filming. We used almost no lighting beyond that of the miners' lamps and a couple of car headlights, again to create that sense of claustrophobia that they lived through.
It was very moving working with their fellow miners - not actors - and watching them really get involved in the story and the emotions the 33 had experienced.
When we rigged up the probe - the moment they were discovered - the "actors" emotions were genuine. They really had come to identify.
But, of course, every night it was quite a relief after 10 hours down the mine in the dark, and the heat, and the dust to get out. Something, of course, the miners themselves could not do.
Angus Macqueen is the director of Chilean Miners - 17 Days Buried Alive.
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