The sex scandal that has transfixed Northern Ireland in recent days has a cinematic echo: a 60-year-old Mrs. Robinson who was caught in an affair with a man who was 19 at the time, and is now at the center of a scandal that threatens to bring down the power-sharing government that has steered the province out of 30 years of sectarian bloodshed. Predictably, local newspaper headline writers and bloggers have resorted to catch phrases like 'Here's to you, Mrs. Robinson,' borrowed from the song made popular by the 1967 film 'The Graduate.' But the storyline unfolding in Belfast has a more serious edge because this Mrs. Robinson, Iris, a stridently moralistic lawmaker, is the wife of the province's loyalist first minister, Peter Robinson, who is now struggling to keep his job. The revelations come at a critical time, when the mostly Protestant loyalists and mostly Catholic republicans are in increasingly bitter discussions about how to put in place the last and most difficult piece of the U.S.-brokered power-sharing agreement: the transfer of police and justice powers to the unity government. The transfer would be a step of historic significance for republicans, who viewed the police as a paramilitary arm of the loyalists during the 30 years of 'the troubles' that left 3,500 people dead. But it raises alarms among loyalists, who fear that republicans will not adequately pursue and punish militants who have rejected the unity government and mounted a deadly campaign of bombings and assassinations in recent months. Peter Robinson's fate is crucial to the future of the agreement; as negotiations have dragged on 18 months beyond the deadline for transferring police power, both sides have become more entrenched in their positions. If Robinson were forced from power, analysts say, there would be little chance of any new loyalist leader risking the wrath of his followers by moving ahead with the deal. When the leaders of the shared government left for their Christmas break in a state of angry impasse, both sides warned that the shared government could collapse early in the new year. This has been a time of equal-opportunity scandals for the loyalists and the republicans, divided through history over whether the six Protestant-majority counties of Northern Ireland should remain part of Britain or become part of the Catholic-majority Irish Republic. Just as the loyalists have been damaged by the revelations about Iris Robinson's affair, republicans have been struggling to absorb recent disclosures by Gerry Adams, their pre-eminent political figure, of a history of sexual abuse within his family. Those include episodes of pedophilia by his late father -- a republican icon -- and investigations of a brother accused of molesting his own daughter. The shock of the revelations about the family lives of the Adamses and the Robinsons has hit especially hard because Northern Ireland remains a world apart from Britain, with its more laissez-faire social and sexual attitudes. With the recent decades of violence across the province entrenching many people in their faiths, Catholics and Protestants alike have hewed to the sterner moral codes of an earlier age. Politicians flouting those codes have done so at their peril. Last week, an emotional Peter Robinson told reporters that he learned of his wife's infidelity only on the night last March when she tried to commit suicide over the affair, by means he did not disclose. But the sympathy he earned turned to demands for his resignation when a BBC documentary on Thursday revealed that Iris Robinson had taken $80,000 in secret loans from property developers to finance her lover's investment in a cafe near Belfast, the province's capital. Neither she nor her husband had reported the loans to the Belfast assembly or the British Parliament, where the Robinsons each hold dual seats. For now, Peter Robinson's survival as first minister depends on an investigation of the loan deal by an independent counsel, yet to be named, whose appointment Robinson promised on Friday night. He said he learned important details about the loan only from the BBC documentary, and added, 'I don't believe that I have done anything wrong.' When Iris Robinson went public last week with an acknowledgment of her affair, she announced her withdrawal from public life, and asked forgiveness of her husband and the public. 'I am so, so sorry,' she said. Her former lover, Kirk McCambley, now 21 and the successful co-owner of the cafe financed by the loans, has given a series of interviews saying the affair began when Iris Robinson befriended him after his father died of cancer. 'She was there to help,' he has said. On Monday, political life will revive in earnest with the resumption of the fractious provincial assembly at Stormont, the imposing neo-Classical-style Parliament building that sits high on a hill overlooking Belfast. The issue of the transfer of police power has become deeply personal for the two men who lead the Belfast government: Robinson and Martin McGuinness, a former chief of staff of the Irish Republican Army, the paramilitary group that put its weapons away to support the government. McGuinness works in close partnership with Adams, who is president of Sinn Fein, the republican political party that maintained a close but shadowy relationship with the IRA throughout the years of violence in the province. Robinson and McGuinness have made little secret of their personal dislike for each other. In a recent interview in Belfast, Robinson spoke of his disdain for the idea of handing power over the police to men who 'bombed and butchered' their way to power, a formulation that sounded as though it had been crafted to refer to McGuinness, who started his adult life as a butcher's apprentice. McGuinness was less personal, but brusque. 'I can get along with anybody,' he said. 'I think I have conducted a respectful relationship with Peter Robinson, but I can stand up for myself as well.' The mood is a far cry from that of the first year of the power-sharing deal, when the government was led by McGuinness and the grand old man of right-wing loyalist politics, the Rev. Ian Paisley. Together they became known in the province as 'the chuckle brothers' for their cheerful acceptance of each other and their efforts to make power-sharing work. But when Paisley resigned after a year at the age of 81 and handed his job to Robinson, the mood deteriorated, with Robinson increasingly beleaguered by right-wingers within the loyalist movement who see the power-sharing deal as a betrayal, and McGuinness under pressure from the rising threat of dissident republicans. Under the rules of the power-sharing agreement, if Robinson resigns over the scandal, McGuinness, too, will be forced from office. That would push efforts to construct a new leadership into the assembly, where mutual recrimination between loyalists and republicans is running high, and where both sides are eyeing the possibility that an impasse on the agreement could force new provincial elections. In that climate, political experts in the province say, it might take months, or even years, to reconstruct a power-sharing government, leaving the British government once again to administer the province by decree. 