Art Keller, a blond, blue-eyed CIA agent, sits inside a decrepit building deep inside al-Qaeda territory, staring at his computer screen. He is forbidden by his Pakistani minders from venturing out into the badlands of Waziristan to help to find and kill the world’s most wanted man.
He is sick and exhausted, and suffering from food poisoning. Back home in the US his father is dying of cancer. The plumbing is basic, the heat intense — the generator has failed again.
He pores over cables looking for any scrap of information — an intercepted phone call, an aerial photograph — that might finally end the hunt for Osama bin Laden.
The fruitless search has essentially been outsourced by the US to a network of Pashtun spies run by the Pakistani intelligence services.
Mr Keller was one of an estimated 50 to 100 CIA agents and special operations officers whose mission for the past eight years has been to find and kill bin Laden and other top al-Qaeda leaders in the hostile and forbidding Pakistani border region, where he is believed to be hiding.
Mr Keller, 39, volunteered for the bin Laden team and was sent in 2006 to become acting chief of one of the CIA’s bases in the heart of al-Qaeda and Taleban territory in Waziristan. It was an experience that leaves him wondering today if the al-Qaeda leader will ever be found.
Mr Keller was not an obvious choice for the job — he spoke no Middle Eastern languages, and was not an expert on al-Qaeda or Pakistan. Yet in 2006, with many resources diverted to Iraq, the CIA was desperate for agents to join the hunt.
Today this is changing. The agency is bringing back CIA retirees — a group known as The Cadre — many of whom are veterans who worked with the Afghan Mujahidin during the Soviet occupation in the 1980s.
Mr Keller’s replacement when he left Shawshank — the nickname given to his base in Waziristan because it resembled the prison life depicted in The Shawshank Redemption — was one such man, a grey-haired, CIA veteran, 65, who speaks Pashtu.
“Some of these guys have been hunting bin Laden for years,” Mr Keller says. His replacement, whom Mr Keller believes is still in Pakistan, has spent eight months a year since the September 11 attacks working out of these CIA safe houses looking for the top al-Qaeda leadership.
“One of the things the agency has done is to bring back these old hands,” Mr Keller says, men who despite their age “are willing to spend many months in conditions most people would say is akin to prison”.
Mr Keller, who has retired from the CIA and is now a freelance writer in New Mexico, adds: “The divorce rate is very high — it’s through the roof. Yet it’s part of the allure that keeps on driving them back.
A lot of the time you are just sitting there reading stuff but you are also in the right area, it’s the big show — you are at retirement age but are you really going to sign up for the bowling league?”
The hunt for bin Laden is largely run by the ISI, the Pakistani intelligence service, an organisation for whom many CIA officials harbour deep mistrust because of its historical ties to the Pashtuns of Waziristan.
Mr Keller says the nerve centre of the hunt is in Islamabad but the ground operation is run from decrepit bases such as Shawshank.
The hub of the operation was the communications room, from where he worked alongside officials from other branches of the US intelligence agencies.
Here they would pore over intelligence collected from electronic intercepts, aerial photographs taken by unmanned drones, and human intelligence collected by Pashtun spies. CIA agents were rarely allowed to leave the compound by the Pakistanis.
One reason was that blond-haired agents such as Mr Keller would be targets for assassination. The other is that the Pakistanis like to have control of the hunt. Any spying was done by local Pashtuns, and under the watchful eye of the Pakistani authorities.
“Our role in the hunt was done entirely from in front of a computer inside the base,” Mr Keller says. When he wanted to follow up a lead, he would get in touch with a local Pashtun proxy to ask him to travel to a certain area to glean information.
It is dangerous work. In 2005 the CIA recruited a local mullah to go into Waziristan to report back on any Arabs in the area — a sign that bin Laden, a Saudi, could be near by.
Days later the mullah was found on a roadside, beheaded, a message tucked into his shirt that this was the fate of spies.
When a senior al-Qaeda figure was identified and located — Mr Keller said that it would take weeks, often months, to build a case for an airstrike by a US Predator drone — and even if the go-ahead was finally given by CIA headquarters in Langley, Virginia, the Pakistanis still had to approve.
“Since 9/11, with 99 per cent of these strikes, the Pakistanis were consulted and they have to approve them,” he said.
There has not been one credible lead on bin Laden in years.
His nickname among some CIA hunters is Elvis because of all the bogus and fanciful sightings. The CIA has been successful in killing many of the senior al-Qaeda over the years but bin Laden and his deputy, Ayman al-Zawahiri, are different cases.
Mr Keller believes bin Laden moves from village to village in Waziristan. He communicates perhaps just once a month, and by courier.
He never uses a telephone. Mr Keller believes that bin Laden arrives in each village with a small group of bodyguards, when he will sit and talk to the local tribal leader. A large bribe is paid.
Bin Laden is then the guest of the village, where under Pashtun custom, he must be protected. The main obstacle in finding him, Mr Keller says, is that even if someone wanted to betray him — and collect the $25 million (£15 million) reward — there is no one to turn to. The local police know bin Laden is there.
“If you report bin Laden’s location there is a good chance you will get killed,” Mr Keller says.
“People in a position to give information can’t get it to anyone.”
Morale is still good among the hunters, he says, because many top al-Qaeda officials have been killed. So will bin Laden be caught? Mr Keller lets out a deep breath. “I don’t know.”