The two men will be demanding justice for the victims of Italy's worst terrorist atrocity, the 1980 Bologna railway station bombing. They represent the families of the 85 people who died when a huge blast ripped through the second- class waiting room on a sweltering morning in August.
Many of the victims were students on holiday. The pictures of weeping rescue workers and mangled bodies - some blown under trains, some in beach-wear for the holiday they would never have - shocked Europe.
Tomorrow's special appeal hearing is the culmination of a legal tale that saw 13 people convicted in 1988 of involvement in the massacre, only to be cleared at a first appeal two years later. Those convicted in the original trial included four young neo-fascists, given life sentences for planting the bomb, two secret service officers and Licio Gelli, grand-master of the banned P2 Masonic Lodge.
With extraordinary tenacity the Association of the Relatives of the Victims geared up for a campaign to keep the issue in the public eye. They lobbied Italy's Supreme Court for the right to have the case reheard. Early last year, perhaps infected by the new reforming spirit seizing Italian public life, the Supreme Court annulled the decision of the appeal court and ordered a new trial.
Since the original trial, evidence has emerged that points to an unholy alliance of right-wing forces, corrupt politicians and secret service agents bent on undermining democracy to hold on to power in the name of the fight against communism. Bologna's place in this process has become clearer. The blast, in a political stronghold of the Communist Party, a well-run, prosperous city, was the climax of a series of atrocities between 1969 and 1984 - an era which became known as the 'Years of Lead'.
The attacks, usually bombings aimed at slaughtering as many civilians as possible, were initially blamed on the extreme left. Now it is accepted that they were part of a 'Strategy of Tension' intended to scare voters away from western Europe's most popular communist party and into the arms of the Christian Democrats.
One of those who will be following the proceedings in Bologna is a retired civil servant from Bath. Harry Mitchell and his wife Shirley lost their daughter Catherine, 21, who died in the blast with her boyfriend, John Kolpinski, from Bristol. Like many people of her age, she was inter-railing around Europe after finishing university.
'I heard about the blast on the radio, while I was gardening, but we didn't connect it with them. We didn't realise they had stopped off at Bologna,' Mr Mitchell says. 'It was a couple of days before we were told that, yes, they thought they had found her.'
A stocky, dapper man, fond of his huge garden, Mr Mitchell has undertaken an almost obsessional quest to learn as much as possible about the forces behind his daughter's death. Boxfile after boxfile in his neat semi-detached home contain cuttings on the outrage.
Less than 150 miles away lives one of the subjects of his correspondence, Roberto Fiore, a prominent Italian neo-fascist. Fiore runs an employment and accommodation agency for foreign students in London, where he has lived since the attack in Bologna.
Although he is not in any way implicated in the massacre, investigators believe he may be able to give them valuable information. He belonged to the political wing of the neo-fascist group whose members were convicted of planting the bomb. But Fiore denies that he knew them. 'I had nothing to do with those people,' he said when contacted at Meeting Point, his office in Kensington.
An Italian attempt in 1982 to extradite Fiore, and a fellow neo-fascist, Massimo Morsello, failed when British magistrates ruled there was insufficient evidence to support the charge on which they were wanted: subversive conspiracy and membership of an armed gang. In 1985, an Italian court sentenced them in absentia to nine and 10 years respectively.
'We were convicted only of belonging to a group not recognised by the state. That is not a crime here,' said Morsello. He does not deny the pair are fascists, but says their political activity is a thing of the past. 'Of course I wanted to subvert the state when I was 18, but I can say categorically that we never broke the law.'
But they may yet be forced to return to the past; Italy has renewed the extradition request, and both governments have reopened proceedings.
In 1984 a convicted neo-fascist, Vincenzo Vinciguerra, was questioned by Bologna investigators. He testified that he had been recruited for an earlier car bomb attack near Venice by Gladio, a shadow army set up by the Italian secret services in the 1950s as part of a Nato plan to create guerrilla resistance in the event of a Soviet invasion or communist takeover in Nato countries. By the time Vinciguerra carried out his attack, in 1972, Gladio was considering pre-emptive action against the increasingly popular Communist Party, according to General Gerardo Serravalle, the secret service chief in charge of the Gladio network.
Forensic reports demonstrated conclusively that explosive from one Gladio arms dump had been used in the Venice car bombing. In Bologna, says Mr Trombetti, experts concluded that the blast, which demolished one wing of the station, was caused by 'retrieved military explosive'. He is reluctant to be more specific but says one can draw one's own conclusions.
Even if the victims' lawyers win their case, some of the real authors of the Bologna outrage will never be brought to justice. But the outcome of the trial will be seen as a symbol. 'Another 'not guilty' verdict would be an insult to the just process of law,' Mr Giampaolo says. 'We may not have all those responsible for this outrage, but we believe we have enough evidence to convict the accused. The public wants the truth on this massacre.'