Laplasse, now 70, works his tall frame into a small wooden armchair. The Belgian press recently carried a photograph of him sitting in this same chair, raising an arm in a Nazi salute.
As the old man stares down at the threadbare carpet, a mangy dog chews at scraps under the kitchen sink. In the yard outside, his budgerigars rattle at their rusty cages.
"Yes," he says eventually. "I worked for the Nazis." He grins and squints defiantly through thick glasses. "But so did everyone in Oostduinkerke. The town was occupied. The Germans were the only ones who had any work here during the war. If I was a collaborator, so were all my neighbours."
It is not just Laplasse's wartime behaviour that has provoked moral soul- searching in Belgium. Far more painful is the question of his mother's involvement with the Nazis. On a shelf above the gas fire is a charcoal drawing of a youngish woman with dark, bobbed hair and proud, strong features. The picture is propped up beside piles of yellowing pamphlets bearing Flemish nationalist insignia: AVV, All for Flanders, and VVK, Flanders for Kristus.
On a fateful day in September 1945, Irma Laplasse betrayed the Belgian resistance to save her son's skin. That is the allegation made against her by Fred Laplasse's neighbours, the sons and daughters of the town's dead resistance fighters.
"She was guilty, we all knew it," says Georgette Torrelle, whose twin brothers, Jean and Polydor, died that day, aged 19. She remembers the entire Laplasse family as les noirs - the blacks, the collaborators, the enemy.
Raise those accusations with Frederick and he throws another of his sullen stares and says: "I don't care what my neighbours say. I have nothing to do with the people of this town.
"My mother was a Flemish farmer's wife. She was a mother of three children. She committed no crime. So what if she was friendly with the Germans? Their headquarters was across the fields." He points through the window, across the road, towards a field dotted with holiday homes.
"She took them milk and eggs. Of course she had German friends. But should she be executed for that? They shot her by firing squad at dawn. Then they sold our animals and land and gave our money to those people - to the resistance," says Laplasse.
The events at Oostduinkerke at the close of the war are a terrible scar in Belgian history. This morning in the Belgian High Court that scar is to be torn apart. The case of Irma Laplasse, a farmer's wife who was executed as a collaborator after the war, is to reopened. She was shot at dawn by a firing squad in Bruges in May 1945, having been found guilty not simply of collaboration with Belgium's Nazi occupiers, but of action that specifically caused the death of seven members of the Oostduinkerke resistance just hours before the liberation of the town by Allied forces.
On 8 September 1944, as news came that Canadian troops were landing on the beaches, the coastal town's resistance fighters rounded up collaborators and held them in the local school. Among the captives was Fred Laplasse. The German garrison was alerted and attacked the school, killing seven resistance fighters and freeing Laplasse.
Marcel Cloet, president of the town's brigade of veterans, recalls that he had woken up that day expecting the Canadians to arrive at any moment. He and others had put up the Belgian flag to welcome them. "But I had a sense that something terrible would happen when I saw them rounding up the collaborators. A friend came by on a bicycle, screaming: "The Germans are coming, the Germans are coming." I tried to take the flags down. Then I heard an explosion. I knew the Germans had hit the school."
The Canadians arrived a few hours later. Fred Laplasse and other collaborators were recaptured. But Oostduinkerke's liberation had been marred by tragedy.
In the investigations which followed, Irma Laplasse was accused of tipping off the Germans about what the resistance were doing that day, in order to save her son.
After the execution, the case became a cause celebre for the Flemish extreme right. Neo-fascist parties such as the Vlaams Blok portrayed Irma Laplasse as a martyr, a victim of Belgian justice, and her case became emblematic of their nationalist fight. Karel Van Isacker, a historian and supporter of the Flemish extremists, researched the case and recently produced new evidence suggesting that Irma Laplasse may have been wrongly charged. Van Isacker is a member of the Jesuit order, part of a Catholic church that was in cahoots with Flemish collaborators throughout the war. With the new evidence,nationalists pressed for the case to be reopened. Earlier this year the government agreed.
Revisiting the events of September 1944 has traumatised Oostduinkerke, but the reverberations of the Laplasse affair go beyond this quiet seaside town. The issues raised could deepen the rifts in Belgian society, threatening the government's efforts to hold together the Dutch-speaking community of the north with the French-speaking Walloons of the south.
Conscious of the divisive implications of the case, the Belgian justice minister consulted widely before ordering a review. Among those he contacted was Arthur Houlot, founder of the Belgian resistance and a survivor of Dachau concentration camp, who was made a baron two years ago for services to the state. Though it pained him, Houlot says he advised the minister that the appeal should go ahead.
"We fought the Nazis for the sake of Belgian justice and democracy. If the law in our democratic state says something may have been done wrong, we must put it right.
"But let nobody forget that collaborators were criminals and bandits who wanted nothing but the destruction of Belgium. We hate them with all our might. They are responsible for the deaths of thousands of Belgians. They helped to send Belgian Jews to the gas chambers."
Whatever the truth about that September day, there is no doubt that Irma Laplasse was a collaborator, as were all her family, and many others like them. While the vast majority of Flemish Belgians were patriots during the war, and many lost their lives at the hands of the Nazis, nationalism and opposition to Belgian rule has always existed among the Dutch-speaking communities of northern Belgium. Their Flemish nationalism is rooted in long-standing bitterness over the treatment meted out to Dutch-speaking communities by the French-speaking elite, who ruled the state in its early days and refused to recognise the Flemish language or culture.
Irma Laplasse's husband, Henri, served with the Belgian forces on the front line just south of Oostduinkerke in the First World War. Like many other Flemish soldiers, he returned embittered by his treatment at the hands of French generals. He joined a far-right fascist group called the Vlaams National Verbond, as did his wife and children. When the Germans occupied the town, the Laplasse family were ready Nazi sympathisers.
Since the war, the enmity and distrust between the villagers had been partially buried. Flanders has won a wide degree of autonomy, and the town of Oostduinkerke has prospered as a resort. It is a favourite spot for Germans to buy holiday homes.
The events of 1944 have been written into history, on neat little plaques around the town. Tourists passing the school may see the memorials to the resistance fighters who fell here on 8 September 1944. The plaques bear the lion's emblem of the "GL", the secret army. The graves of the seven lie in the nearby churchyard.
The forthcoming trial threatens to tear asunder all this studied reconciliation and revive the hatred. For years the villagers have learnt to ignore Fred Laplasse's presence. But recently they have seen him on television, extolling the virtues of the Nazis, saying Hitler "didn't go far enough with the Jews". Now the families shudder again at the sight of their neighbour. "I have the video. I saw him say it," says Jeannine Ureel, who was seven when her father, Leopold, was killed in the school.
In the neat salons of these quiet streets, strangers are distrusted. "You are from the other side - from the blacks?" we were asked by a member of one of the victims' families. There are many in Oostduinkerke who do not want to talk about the case - who dare not, knowing that their own family may have Nazi skeletons in the closet.
"We have always known which were the collaborator families and which were not," says Jeannine Ureel. "We didn't forget, but we have tried not to talk of it for all these years. Now we are talking about it again - but it is not our fault.
"It was not the victims' families who stirred this up. I wrote to the King to say the trial must not happen. It is too much for the victims' families to take. He wrote a kind letter back," she says, helplessly.
As the appeal begins today, the villagers of Oostduinkerke and the Belgian establishment are braced for the possibility that Irma Laplasse may be found not guilty posthumously. Then, as everyone knows, the nationalists will launch their next campaign, demanding a blanket amnesty for the thousands of collaborators who were convicted by courts after the war. The Vlaams Blok has already made its intentions clear, staging a march through Oostduinkerke on Saturday to call for such an amnesty.
"It can never come to that," says Baron von Houlot. "Amnesty would mean just washing away the past. It would mean we fought and died for nothing. It would mean the Nazis were not criminals and there were no crimes. An amnesty would mean revolution."