Brendan Duddy is an ordinary man from Derry who, for more than 20 years, was at the centre of extraordinary events that eventually led to the historic IRA ceasefire of 1994 and the Belfast Agreement.
Brendan Duddy gave an extensive interview to the BBC
During that time his identity was kept a closely guarded secret by those with whom he dealt - representatives of the IRA's ruling army council and British intelligence officers from MI6 and MI5.
Until now, he's only been referred to as "The Link" or "The Contact", the secret intermediary whose aim was to bring the two sides together to end the conflict.
I have known Brendan for more than 10 years and he promised he would give me his first television interview one day when the time was right. He's decided that time is now.
Making peace in the shadows is a dangerous business, especially in dealing with an intensely suspicious and secretive organisation like the IRA.
Brendan survived because he'd built up a track record of trust with both sides.
His role as embryo intermediary began in Derry in January 1972 in the days leading up to Bloody Sunday when, at the request of city's chief police officer, Frank Lagan, a Catholic and friend, he persuaded both the Official and Provisional IRA to remove their weapons from the Bogside.
This they did but, unbeknown to Brendan, the Official IRA left a few behind for "defensive" purposes.
No-one, least of all Brendan, foresaw the tragic outcome of that day.
After 13 unarmed civil rights marchers had been shot dead by British paratroopers, he warned Mr Lagan: "This is absolutely catastrophic. We're going to have a war on our hands."
Brendan's role as embryo intermediary began in 1972 in the days before Bloody Sunday
Brendan was right. From that point on he dedicated himself to trying to bring that "war" to and end.
Later that summer, on the eve of Operation Motorman, the Army's full frontal assault on the IRA's "no-go areas" in Derry, he again facilitated the removal of IRA weapons to avoid a repetition of Bloody Sunday.
He was not prepared to say how it was done, except to admit he faced a moral dilemma.
"I was aware those weapons probably had killed people. I felt it was part of a process. I had to do it."
He said 54 guns were collected.
Brendan's life was about to change in 1973 when the British government official, Michael Oatley, arrived in Derry.
Brendan was to become the secret link between the British and members of the IRA's ruling army council, passing on messages from time to time via Oatley from one side to the other.
The close relationship between the two men worked because both shared the same goal: to persuade the IRA to end violence and embrace politics.
Martin McGuinness met William Whitelaw after Bloody Sunday
Both agreed on the same premise - that the British were never going to cut and run and abandon 1m Protestants and they saw eye to eye on the same precondition: that political progress could only be achieved once the IRA had ended its campaign.
It was to be 20 years and more than 2,000 deaths later before the IRA came to terms with those realities.
After months of groundwork, Brendan and Oatley's first achievement was persuading the IRA to declare a ceasefire and enter secret talks with the British in 1975. It wasn't the first such encounter.
Three years earlier, in the aftermath of Bloody Sunday, senior republicans, including Martin McGuinness and Gerry Adams, had met the Northern Ireland Secretary, William Whitelaw, at a minister's house in Chelsea's Cheyne Walk.
The meeting got nowhere as the IRA gave the British three years to pull out of Northern Ireland.
"It lasted an hour. It was a disaster," says Brendan. "'Brits Out' politically couldn't happen. It was the result of the IRA's lack of understanding of politics at the time."
Brendan had to convince the IRA that the British wanted talks
To start the process again in 1974/5, Brendan had to convince the IRA's army council that the British were seriously interested in dialogue.
On New Year's Eve, he was driven to a secret location in the Dublin area where the handful of men who ran the IRA's campaign were meeting in an impressive country house.
"I went into an enormous drawing room and there were these men round this table, a board of governors, just like ICI."
One of the "governors" was the Belfast IRA commander, Billy McKee. McKee was astonished to see a total stranger being brought into the room as such meetings of the IRA's leadership were sacrosanct.
"It wasn't on the books to bring anybody to an army council meeting,?" McKee, still a fiercely dedicated republican in his 80s, told me.
"He looked bloody scared when he came into that room."
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Brendan convinced his formidable interlocutors of his good faith and said he would facilitate the meetings with the British on condition that he handled security.
The meetings were to be held at his house in Derry and IRA leaders were secretly driven across the border by his close friend and neighbour, Bernadette Mount, who was to play a vital role in the years ahead.
When Bernadette and her passenger came to an Army check point, she hid any potentially incriminating IRA documents inside her jumper.
IRA leaders like Billy Mckee and the IRA's chief of staff, Seamus Twomey, stayed at her house as did the president of Sinn Fein, Ruairi O' Bradaigh.
Bernadette still has a photograph of O'Bradaigh in his Paisley pyjamas.
The talks between the IRA and the British continued throughout 1975 but the IRA's mindset of 1972 had not fundamentally changed.
Suspecting a backdoor deal was being cooked up by the British, loyalist paramilitaries unleashed a campaign of sectarian killings.
The IRA retaliated, the ceasefire was over and the talks ended. They were a watershed in the IRA's history.
Gerry Adams, who'd been in jail at the time, and Martin McGuinness, who'd just been released from prison in Dublin, were poised to take over the leadership of the IRA.
They accused their predecessors of being duped by the British. Today Billy McKee believes it is they who have been duped.
It was to be another 15 years, beyond the trauma of the 1981 hunger strike in which 10 republican prisoners died, before things started to move again.
The Secret Peacemaker will be broadcast on Wednesday 26 March at 2100 GMT on BBC Two.
The programme will be shown in Northern Ireland on Thursday 27 March at 2100 GMT on BBC Two.