The journalist was also the focus of protests by extreme right-wing groups, apparently at the behest of some shadowy nationalist who had taken offence at his reporting of the imperial family, although there was no way that could be linked to Obara. Most worryingly, a letter that accidentally came into his possession encouraged the extremists it was meant to reach to seibai Lloyd Parry. Seibai is the term used in period dramas on television for how a samurai deals with his enemy, usually with a sword.

The package also included photos of Lloyd Parry that had been taken surreptitiously and the police warned him to be careful, and not to stand too close to the edge of the platform when waiting for a train. 'The next few weeks were like a hallucination,' he says. 'One of the things I love about Japan is that because it is so different you notice things, but after 10 years you tend to stop doing that. But when you're on the lookout for an assassin you get all that freshness back. I found myself remembering licence plate numbers, people wearing dark glasses - it was... quite eerie.'

The libel suits, which were dismissed, were a costly inconvenience to Lloyd Parry and The Times, his employer, but were nothing to what Obara put the families of Lucie Blackman and earlier victim Carita Ridgway through, as well as the handful of women who could be located to testify against him and the hundreds of other women who were seen naked and apparently comatose on video tapes found in his apartments.

'I struggle to find a silver lining to the story as it was just misery piled upon misery upon misery,' says Lloyd Parry. 'The waves of pain radiated outward.'

Blackman's sister Sophie attempted suicide; Rupert, her younger brother, suffered a breakdown and dropped out of university; and Jane, her mother, appeared at times on the verge of a meltdown. Only her father, Tim, appeared to be functioning normally, but Lloyd Parry knows that was, in part, a facade. When Blackman was still missing Tim's energies were channelled into devising new ways to find her and chivvying the police on. After her body was found in early 2001 buried in a small beach cave close to one of Obara's apartments south of Tokyo, he focused on ensuring his daughter got the justice she deserved.

The story was made more poignant by the barbed exchanges between Tim and Jane, who had divorced acrimoniously some years before Blackman went to Japan, and Jane's malevolence reached new heights after she learned Tim had accepted GBP50,000 (HK$5.6 million) in 'condolence money' from Obara while the trial was still going on.

'I don't think I was so critical of them [in the book],' says Lloyd Parry. 'I realised early on, and this is no more than stating the obvious, but they were all victims of a horrible crime. That got lost in the media coverage, especially towards the end, when the media got caught up in the issue of the 'blood money'. They lost sight of the crime and treated it as a battle within a family.'

Blackman, her family's reaction, the blase attitude of young Western women in Roppongi, the curious background and life of Obara, the police investigation - initially more farce than effective - and some curious judicial procedures all combine to make the case uniquely rich. Lloyd Parry says it 'got under his skin' and that he learned a lot about a country he thought he knew fairly well. The only person he didn't come close to grasping was Obara himself.

'That stance in court of turning three-quarters away from the public, so even the court artists could never get an image, that was symbolic of him,' he says. 'He went through life hiding traces of himself. I [visited] Osaka to try to find out more about him and his family, but there was nothing. His father was one of the richest men in Osaka, but no-one remembers him. I talked with the Japanese tabloid journalists who knew all the tricks and they said they had never seen a case like this. Usually someone in the family talks, or a boss or a neighbour or a friend - but there was no-one. Obara was an incredibly secretive, isolated and lonely person by his own choice.'

After the trial and a series of appeals, Obara was sentenced to life in prison in April 2007. That usually amounts to a tariff of 30 years, of which he has already served about a decade during the hearings.

He never admitted anything in court and fought the prosecutors tooth and nail. 'This is a serial rapist and an extraordinary personality that was demonstrated during the trial,' says Lloyd Parry. 'He had an iron will to fight everything in court in a legal system in which people usually just roll over and confess.'

That refusal to confess stymied the police, for whom the journalist reserves special scorn. Not only were they slow to react to Blackman's disappearance, but it also became clear they could have stopped Obara in 1992 when Carita Ridgeway was dropped off at a hospital by a man who gave a false name and left. She went into a coma and never regained consciousness. 'The police should have shown more curiosity and Obara could have been stopped there and then, eight years before Lucie's death.'

Lloyd Parry's other conclusion is that had Tim Blackman not defied the police and stood on street corners with posters of his daughter and courted the media, the police would have dropped the search and Lucie's remains would not have been found. And Obara would still be prowling Roppongi.

Not that much has changed in the hostess clubs and strip bars there. 'Roppongi hostess bars are supermarkets for date rape,' says Lloyd Parry. 'The girls are on the shelf for a predator to pick off. There is a financial incentive for them to get into the car of a man they hardly know and if they don't accumulate enough dohan [arranged] dates then they lose their job.'

He gives the shrug not of a man who does not care, but of a man who has arguably done more than most to point out the problem yet remains frustrated that what is known locally as 'the water business' still flows unabated.