In 2007 and 2008, Outpost Restrepo in Afghanistan's Korengal Valley was one of the most dangerous places on earth.
The platoon of American soldiers from Battle Company of the 173rd Airborne Brigade were stationed on the ramshackle base, which was named after fallen US medic Private Juan Restrepo. They regularly came under Taliban attack several times a day, often from close quarters.
They had virtually no amenities and little contact with the outside world. Their world largely consisted of sandbags, their weapons and each other.
"Nobody's going to help you there - you're in no man's land," says Specialist Sterling Jones of the outpost.
Although reinforcements were stationed less than a kilometre away, "that might as well be a different country because they're not getting to you," says Specialist Jones.
'Valley of death'
Award-winning British photographer, Tim Hetherington, and best-selling American author of The Perfect Storm, Sebastian Junger, chronicled Battle Company's gruelling 15-month tour of duty.
"We went to the Korengal in May 2007 and we asked the commander where the brunt of the fighting was," says Tim Hetherington.
"He pointed down the valley and said, 'Second Platoon'."
At the time, the fighting in the valley was so intense that nearly three-quarters of all the bombs dropped by Nato forces on the whole of Afghanistan landed around a strip of territory just six miles long and half a mile wide.
More than 40 American soldiers died in the Korengal Valley and many more were wounded before US troops began withdrawing from the area late last year.
Between them, Hetherington and Junger spent 10 months in the Korengal and their documentary, Restrepo, is released in British cinemas Friday, 8 October.
The film received critical acclaim when it was released in the US earlier this year and is being mooted as a possible Oscar contender.
"We wanted to make the most experiential and visceral war film we could," explains Hetherington.
"We were, to all intents and purposes, part of the platoon, apart from carrying a weapon and pulling guard duty."
Embedded in danger
Using small, low-cost digital cameras, Hetherington and Junger were able to capture the chaos and fear - as well as the boredom, intimacy and even humour - of modern combat.
They witnessed first-hand an American Humvee hitting an improvised explosive device as well as troops wrestling playfully with each other while dance music booms out in the background. In one of the film's most striking scenes an American soldier sobs uncontrollably over the death of a friend during an operation against the Taliban.
"Filming those events was very tough," admits Hetherington.
"At one point one of the soldiers shouted at me to stop filming because he was so upset. Later I found him smoking a cigarette. He turned round to me and said he was sorry he'd asked me to switch off the camera and that he appreciated me being there."
Inevitably, close bonds formed between soldiers and film-makers.
This has led some critics to question whether Restrepo, and an accompanying book of photographs entitled Infidel, is a balanced portrait of the war in Afghanistan.
Some have argued that by focusing so intensely on the soldiers of Battle Company, Hetherington and Junger ignore the wider political context behind the conflict and the views of the Afghan people themselves.
"I don't claim to be objective but that doesn't mean I can't be truthful or honest to the experience," says Hetherington.
"People often wonder why the focus is on the American soldiers but understanding what motivates young men in war, understanding how they are likely to respond and act, is central if you're trying to develop a strategy for peace-building efforts."
Hetherington describes Restrepo as a cinematic Rorschach Test - an abstract canvas onto which the viewer imposes his or her own views.
"The far left feel you're a coward unless you make a moral condemnation of the war and the far right feel you're being unpatriotic if you question its rationale, but those two extremes aren't useful," he says.
"By not saying we're for or against the war but by just saying 'this is what it is' we've actually brought disparate communities from different ends of the political spectrum into a conversation.
"How can we know whether we're doing the right thing in Afghanistan unless we ask questions of ourselves about the risk we're exposing the soldiers to?"
Restrepo is released in cinemas on 8 October. Infidel is published by Chris Boot Ltd. An exhibition of photos from the book is on show at the Host Gallery, London, until 15 October.
Photos and film footage courtesy Dogwood.