Previously unseen footage, to be broadcast in the BBC documentary series Our War, shows how the first major deployment of British troops sent to Helmand Province in 2006 was almost overrun and told to prepare for capture.
In the dead of night, July 2006, British soldiers stood on the roof of their compound in Helmand Province, Afghanistan, and watched a Hercules fly overhead.
The plane was carrying desperately needed supplies of food and ammunition.
But when it finally dropped its cargo, it landed about 2km beyond their base in Sangin - deep in enemy territory.
"Everyone's morale just plummeted," says Sergeant Trevor Coult. "It was just a misjudgement… but quite depressing."
End Quote Sergeant Major Jason Conway
You're fighting on every level... it was proper soldiering”
Sgt Coult, of the Royal Irish Regiment, was one of a small number of British troops sent into Helmand in April 2006, based on reports that the Taliban had returned to the area and were becoming an increasing threat.
The first couple of weeks passed, and although aware they were being watched by local militia, the 30-strong platoon in Sangin were not involved in any fire fights and perceived the general threat to be low.
But suddenly - almost overnight - the situation changed. The Taliban appeared everywhere and began attacking all four British bases in the region.
The fighting lasted months instead of the expected weeks. Troops were trapped and running low on vital supplies of food and ammunition.
"You're fighting on every level," says Sergeant Major Jason Conway. "You're fighting for communications, you're fighting for awareness, you're fighting to see the enemy… it was proper soldiering."
Just getting men in and out of the area was, in itself, a huge operation. "To get relief in place, you ended up having to have about 200 soldiers pushed out around Sangin and they were all in fire fights," recalls Sgt Coult.
The British army - now exposed and vulnerable - had to start thinking of other ways to keep the Taliban at arm's length.
One of the things they focussed on was the Taliban's fear of being filmed.
"We used empty ammo containers and sprayed them yellow or different colours. Then we used to stick poles up in the air and put bottles on the end of them, which looked like antennas. [The Taliban] were under the impression these were cameras," says Sgt Coult.
But such measures, although effective to a degree, were not enough to stop such an unexpected onslaught.
In a statement made in May 2011, General Sir Peter Wall said of the situation: "As is historically the case, it is not until you get on the ground and start braving it out, and really get to know what is what, that your intelligence picture will start to develop much more rapidly. That is historically the case in every conflict, and I have to say that, despite all of our high-techery, it will continue to be so."
Soldiers in Sangin were going for days without sleep, and after the failed drop of vital supplies in the middle of the night, some men were told to prepare for being overrun, captured and tortured.
End Quote Sergeant Trevor Coult
It's the worst place I've ever been to”
Sgt Coult thought they were going to be captured on a number of occasions. But as a full corporal at the time, his sense of responsibility kicked in too.
"If you've got young lads below you and if you are in any sort of command position - even if you're feeling like rubbish - the last thing you want to do is let the guys below you see that you're falling apart. If they look up to you and you're starting to fall apart, then the battle's lost."
Faced with this increasingly dangerous situation, the British military were left with only one option… a massive bombing campaign, in the hope it would drive the Taliban back and save the men's lives.
"When you're on the ground… you know that the bullets are coming towards you and you get down low, but if they're coming from all sides, it's daunting to think there's nothing there to help you. But whenever the jets came in, it was a relief," recalls Sgt Coult.
But the bombing destroyed the homes and lives of many of the local people of Helmand and the soldiers were very conscious of this too. "You know you're inflicting systematic violence to the extreme," adds Sgt Major Conway.
At the end of their tour in Afghanistan, the men were finally able to tell their story of what happened in Helmand.
"It's the worst place I've ever been to," said Sgt Coult when he was interviewed shortly after leaving the area. "Baghdad's like a walk in the park compared to here."
As a result of their experiences in the province, British troop levels were increased, and Helmand quickly became known for being one of the toughest places to be stationed in.
"We all knew at the start that this thing would take a long time," says Sgt Coult. "My guys just didn't think it would be as hard, so quick.
"Everyone's learning a hell of a lot every day there and you learn a lot about yourself… The amount of brave things that everyone does is unbelievable."
Our War, episode two, will be broadcast at 2100 BST on Tuesday 14 June, 2011, on BBC Three.
Watch epsiode one here.
Read more about the series and see over 35 exclusive self-shot films, exploring a decade of conflict in Afghanistan.