Alastair Morgan lives on the top floor of a high-rise building in north London, shielded by a network of locks, lifts, intercoms and buzzers. It makes him feel safe, he explains, since he has developed a habit of asking difficult questions about potentially dangerous people.
In March 1987 his brother, private investigator Daniel, was found dead in a car park in Sydenham with an axe embedded in his head. 24 years later Alastair is still searching for answers, a quest that began just hours after what has become one of Britain's most notorious unsolved murders.
He immediately sought out Daniel's business partner, Jonathan Rees, later named as one of the prime suspects, before speaking to the police, visiting the murder scene and quizzing his brother's friends and associates.
"I think I went into a state of emergency," Alastair says. "I had to stay alert, I had to keep my eyes open. I kind of suppressed everything."
"I was crying in private but it was as though my emotions were numbed and just my head was working."
The following month Rees, his brothers-in-law Gary and Glen Vian and three police officers were arrested in connection with the murder but released without charge - a pattern that would become all too familiar over the next two decades.
We head to a nearby café where Alastair, 62, looks back on his childhood in Wales, a time before life became consumed with bringing the killers to justice and exposing what he sees as a tangled web of lies and cover-ups.
"I was Daniel's older brother, there were 11 months between us," he says. "We shared a room, so I knew him pretty well. He was just my pesky kid brother. He was quite a gregarious, outgoing sort, he liked people." The pair went their separate ways in their early 20s - Alastair to Sweden and Daniel to agricultural college - and started their own families, but always kept in touch.
When Daniel was murdered, Alastair's life changed overnight and he has dedicated himself to searching for the truth ever since - lobbying MPs, giving interviews, attending court hearings, even dealing with death threats.
Alastair's Scandinavian background allows him to work from home as a translator, which gives him time to run the campaign, reading, researching, blogging and tweeting, which he says has become like a full-time job.
"There have been many, many bad days, bad weeks and bad months," he says. "I feel that almost every time the police have done any investigation we have been left in a worse position than when they started. We have found out more about police corruption on each occasion and the situation looks worse and worse each time."
The most recent inquiry looked like it would finally result in a trial, until the case collapsed again in March. A possible motive had emerged - that Daniel was preparing to expose a network of crooked police officers with links to his PI firm - and the Metropolitan Police admitted corruption had scuppered the initial investigation. But the family was told it was unlikely anyone would ever be convicted.
"It was like a slow-motion car crash," Alastair says. "I just thought '24 years of my life I have been fighting for this and it has gone again.'"
Alastair and Daniel's mother, Isobel Hulsmann, has been just as vocal as her eldest son in calling for all the evidence to be reviewed and for the Government to meet with the family.
The 83-year-old, who lives in Hay-On-Wye, said: "My God, I have put some fight into this. It has been hard going, because I have been living off the state all these years.
"I think Daniel would be proud but I don't think he would have wanted us to suffer so much. It has been so cruel and twisted and dirty and grubby. This has not been a straightforward case, but it has been made more complex than it should have been."
She added: "We have pursued this with vigour, vitriol and anger. We cannot give up."
The case was thrust back into the spotlight in the summer with new evidence that the News of the World may have interfered with the original investigation, and the family believe they have been victims of phone and computer hacking.
Along with pressing for a judicial hearing, Alastair has now turned his attention to the Leveson inquiry, which offers daily revelations about alleged corruption and illegal practices within the tabloid press. He speaks passionately and emotionally about how much he has learned since 1987 and says a culture of corruption remains within public institutions.
"I am very distrustful of authority and I think with good reason," he says. "I have realised that our democracy is far more stunted and emaciated than I believed.
"I have given up hope of any convictions. It has been so messed up, I don't think anybody will ever stand trial for Daniel's murder. But the way this has been dealt with by the police and their relationship with the News of the World needs more probing.
"Daniel is gone now and nothing is going to bring him back. It has become bigger than that."