On the afternoon of the handover of Dublin Castle to the Irish Free State, Michael Collins - seldom one to willingly pause for photographs - hurried into Dublin Castle to be met by the Under Secretary for Ireland, James McMahon, once described as the most senior spy in Ireland.
"You are welcome," said the civil servant.
"Like hell we are," Collins replied as he brushed past him.
The business of taking control of the Government of Ireland - in what had been for centuries the citadel of British rule in Ireland - was Collins' sole focus. It would be a hugely symbolic moment for Ireland, emerging as it was from years of revolution, war and social terror.
Only that morning, the first meeting of the Provisional Government had taken place at the Mansion House. It fell to Collins, as newly-appointed Chairman of that Government, to lead the delegation.
He was accompanied by seven other members of the Government, including W.T. Cosgrave, Eoin McNeill and Kevin O’Higgins.
Next to greet Collins and his fellow members of the Provisional Government at the castle, was Lord FitzAlan-Howard of Derwent, the Viceroy. It was his job to fulfil the terms of the Anglo-Irish Treaty - which had only days previously been narrowly and divisively accepted by Dáil Éireann - and make the handover of power official.
Ironically, the British Government lacked a legal basis to hand over anything to a group of men who would become the new Government.
As a way of getting around this, the Provisional Government would be regarded as a committee on whose advise the viceroy would act, until the necessary legislation was passed in London. This allowed Lord FitzAlan Howard to receive the delegation as the king’s representative, and to greet them as new ministers.
Thus, men who - in the eyes of those who controlled the Government departments based in Dublin Castle - had blood on their hands and, until just months before, a price on their heads, came face-to-face with those they regarded as the architects of tyranny.
As the Irish Times noted the following day, after centuries of being under siege by revolutionaries: "Dublin Castle was quietly handed over yesterday to eight gentlemen in three taxi cabs."
It was, according to another newspaper: "Perhaps the first time an officer of the Irish Army entered Dublin Castle, except as a prisoner."
Collins did not immediately reciprocate the welcome extended to him and his delegation by the viceroy when they arrived at the castle.
Indeed, the Belfast Newsletter carried a headline referring to the "Viceroy’s Humiliating Role".
However, Colllins strategically greeted the heads of various Government departments warmly.
These, after all, were men who knew how to run Government departments efficiently, something many of the incoming Government had little knowledge of.
It was some of these civil servants who later provided the most detailed and acerbic accounts of the proceedings.
George Chester Duggan described the incoming Government members as:
"A motley assemblage: some in tweed caps and unpolished boots; others with the beards of yester-eve still fresh on their chins; others with long lanky hair, collars and ties au peintre. Mr Collins himself was first in the door, and though the red carpet had in its time been laid down in the hall and up the stairway for many strange personages, yet surely this was the strangest scene of all it had beheld."
Henry Robinson described Collins as "cordiality itself," moving about the room "with none of the top dog about him. He grasped the hands of civil servants…and shook them warmly with his iron grip."
Mr Robinson also noted that the rest of the Irish Government delegation "all looked pale and anxious and barely out of their teens."
Almost until the moment Collins arrived at Dublin Castle, little of what was about to happen seems to have been confirmed. There was, after all, no precedent for Britain handing over a large part of the territory of the UK on this scale.
One of the few real portents of the impending drama was the burning of files on bonfire in the castle courtyard in the days leading up to the handover.
On the day, there was no public ceremony, nor did a flag fly over the castle. The viceroy was not kept waiting in a plumed hat in the courtyard, as portrayed in Neil Jordan’s movie, 'Michael Collins'.
The proceedings took about 45 minutes in all. The viceroy congratulated Collins and informed the delegation they were "now duly installed" and the process would be completed without delay.
Mr Duggan described the civil servants as being "for the most part ill at ease".
It was, he wrote:
"A scene worthy of a painter, fit for the master hand of some great dramatist. The drama of seven hundred-odd years - was it comedy, farce or tragedy ? - that was about to be played out; the curtain was about to fall on the last act and the last scene. When it would rise again it would not be on the same play."
The "drama", in the words of historian, Martin Maguire, was ultimately a revolutionary event, but not a spectacle.
Afterwards, Collins and the others returned to the Mansion House, where he is recalled as seeking out Arthur Griffith to tell him: "Griffith! The Castle has fallen!"
The British Government later issued what could be considered a relatively magnanimous statement, wishing the Provisional Government "every success" and expressing the hope that "a happy, free and prosperous Ireland would be attained."
Whatever magnanimity had been offered was not reciprocated by the Irish side, which annoyed the British by subsequently referring in a statement to the "surrender" of the castle, which was not fully taken over until the following August.
Collins wrote to his fiancé, Kitty Kiernan, immediately afterwards that he was "as happy a man as there is in Ireland today. My thoughts just now are all with you, and you have every kind wish and feeling of mine. Have just taken over Dublin Castle and am writing this note while awaiting a meeting of my Provisional Government. What do you think of that?"
His euphoria would short-lived, however. By June, Ireland would be embroiled in civil war.
The author gratefully acknowledges the assistance and work of Dr John Gibney and Dr Kate O’Malley of the Royal Irish Academy, whose book: 'The Handover - Dublin Castle and the British Withdrawal from Ireland, 1922' has recently been published by the RIA. All royalties from the sale of the book are being donated to Focus Ireland.
A State event commemorating the handing over of Dublin Castle will be broadcast live on RTÉ 1 television today. Coverage begins at 1.35 pm.