The Bloody Sunday Inquiry's long-awaited report into the most controversial incident in Northern Ireland's Troubles will finally be published on Tuesday, with its findings set to reopen old wounds.
The 12-year-long attempt to collate a true picture of what happened is certain to stir up deep-seated emotions in the province, where peace has held between Protestants and Catholics despite a resurgent paramilitary threat.
The mammoth 5,000-page report examines the events of January 30, 1972 in Northern Ireland's second city Londonderry, when 13 civilians were shot dead by British soldiers at a civil rights march. Another man died later from his wounds.
It was a landmark incident in The Troubles - the three decades of violence in which more than 3,500 people died, which were largely ended by the 1998 Good Friday Agreement.
The longest and most expensive inquiry in British history, which has cost 190 million pounds (275 million dollars, 230 million euros), could trigger the exact opposite of the reconciliation intended by its launch.
The report will be revealed when Prime Minister David Cameron makes a statement to parliament's lower House of Commons at 3:30pm (1430 GMT) on Tuesday. The families of the victims will have had access to it for five hours beforehand.
The inquiry was commissioned by prime minister Tony Blair in January 1998, three months before the Good Friday Agreement was signed, to re-examine the events of Bloody Sunday.
A tribunal headed by John Widgery, the lord chief justice of England and Wales, produced 11 weeks after the incident, had largely cleared the British paratroopers and authorities of blame.
Widgery's strongest criticism was that the firing "bordered on the reckless".
But Blair launched the second investigation, saying the quick timescale meant Widgery was "not able to consider all the evidence that might have been available", while "much new material has come to light" since.
The probe is headed by Lord Mark Saville, a top judge in Britain's highest appeal court.
Blair said that "the aim of the inquiry is not to accuse individuals or institutions, or to invite fresh recriminations, but to establish the truth".
However, the possible outcomes could stoke tensions in a province where the two communities are still not fully reconciled, despite their power-sharing government.
Should Saville adjudicate unlawful killing in all the cases, there will likely be demands for soldiers to stand trial.
If the tribunal decides that only some of the cases were unlawful killing, there could be uproar among families of the victims.
And if he repeats Widgery's verdict, accusations of "another whitewash" will probably dominate.
The Guardian newspaper said it had learned that a number of the fatal shootings would be ruled as unlawful killings.
But the British government's Northern Ireland Office dismissed that as "speculation" that would only add to the anxiety of the families of those injured and the soldiers.
Jonathan Powell, Blair's former chief of staff, told The Times newspaper: "Our experience of inquiries is that they tend not to settle disputes - be they in Northern Ireland or Iraq - just reopen the damn things".
Saville chaired a three-man tribunal, which also included William Hoyt, a Canadian judge who was the chief justice of New Brunswick, and John Toohey, a former justice of the High Court of Australia.
They heard from more than 900 witnesses and received statements from around 2,500 people. The evidence ran to an estimated 20-30 million words.
Among the witnesses was Northern Ireland's Deputy First Minister Martin McGuinness, who admitted to the inquiry that he was an Irish Republican Army paramilitary commander in Londonderry at the time.
The judges retired in late 2004, but those awaiting the report have had to wait since then as publication faced repeated delays.
The report was finalised in March, but there was not enough time to publish it before parliament dissolved ahead of this year's May general election.
Its release comes at a time when dissident Republican paramilitaries opposed to the peace process are "highly active and dangerous", posing a threat at its highest level for more than a decade, according to a watchdog body.
In his opening statement in April 1998, Saville said the tribunal had a "very difficult task in trying to find the truth".
"We are enquiring into matters that have given rise to very strong emotions. Those emotions are wholly understandable, for whatever the circumstances, people were killed and wounded."