In the first three parts, we heard how 33-year-old mum of two Arlene Fraser went missing from her north-east home in a 50-minute window on April 28, 1998.
Grampian Police launched a major probe fearing Arlene had been murdered but were unable to prove by whose hand she was killed.
But in 2002, the Crown Office charged three men with involvement in the crime.
- Nat Fraser – Arlene’s husband, suspected of organising her abduction and murder.
- Hector Dick – The best man at Nat’s wedding, who admitted buying a beige Ford Fiesta linked to her disappearance.
- Glenn Lucas – Nat’s childhood friend who worked with him at a fruit and veg business. Lucas later established his own fruit firm in England and gave Nat help forming his own fruit company in Elgin. Lucas was caught talking to Nat about the crime during a prison visit.
The three were charged with murder, conspiracy to murder and attempting to defeat the ends of justice.
Giving evidence against Nat Fraser
The trial began at the High Court in Edinburgh in January 2003 – but things then took a controversial turn.
A week into proceedings, the Crown dropped charges against Dick and Lucas, leaving Nat as the sole accused.
The Crown took the view that it would be better if Dick and Lucas were used to give evidence against Nat.
Former Detective Superintendent Alan Smith said: “The Crown consulted Arlene’s family about this decision.
“They thought they could go after three people and maybe miss all three or have a higher chance of getting one.
“The family were never in any doubt that the conviction they wanted was that of Nat.
“Hector Dick and Glenn Lucas were a bit of a sideshow.”
Prosecution lawyers spent the best part of a week interviewing Dick before the trial resumed.
Dick took the stand. Much of what he said is impossible to assess as he later claimed that he lied about many elements of the case.
Mr Smith told us: “Dick talked in riddles. You never knew if you could trust what he said.
“When we searched his house (during the investigation), we noticed a sticker on his phone that said ‘think before you speak’ on it. He knew all the tricks.”
Alex Prentice KC, the prosecution lawyer in the second trial, told us: “I seem to remember saying to the jury they would be very slow to accept everything Hector Dick said.
“However, they might be inclined to accept it if there was independent support for what he said.”
During the trial, Dick said Nat had raised the topic of missing people and the low number of “no-body convictions”.
Dick told the court: “Nat mentioned ‘there are 10,000 people a year who go missing and none of them ever get found’.
“He had an ill will towards his wife, so I took it in that context.”
Dick also claimed Nat had used books and computers to research this topic – something that could be independently proven.
Taking the stand in his own defence, Nat – who denied all charges – claimed he loved Arlene and that their marriage was “trying”.
Guilty verdict for Nat Fraser trial
So would the jury accept the prosecution case or Nat’s story?
Mr Smith said: “The bell goes to let you know that that’s the jury ready to come back with their decision.
“It was almost unbearable, the tension.
“I was sat with Arlene’s family. You just don’t know how it’s going to go with juries.”
He added: “The verdict was guilty. It was such a relief and so overwhelming.
“I was politely told to quieten down – I almost got thrown out of court.”
The judge, Lord McKay, jailed Nat for life with a minimum of 25 years, telling him the crime was “something you will have to explain to your two children”.
It appeared Arlene’s family were at last getting some sort of closure.
And they added to that by holding a memorial service on Easter Monday in April 2003 – almost five years after Arlene went missing.
Several hundred people attended the service at St Giles and St Columba’s South Church in Elgin, where Arlene had wed Nat 15 years earlier.
In a statement, Arlene’s family said: “This is our chance to celebrate Arlene’s life.
“We will always remember her as an outgoing, loving and caring mother, daughter, sister and friend.”
Nat Fraser freed from prison
Mr Smith said that despite the conviction the investigation continued.
He added: “Nat was spoken to in prison and given the opportunity to offer up any information as to where Arlene might be. That didn’t go well.
“I was politely told where to go.
“But thereafter, that was largely it because we’d had years of searching for her and there were few lines of inquiry.
“I remember we went up to the Black Isle to excavate a site that had a connection with Glenn Lucas.
“There was an unusual disturbance of earth in this field and I was up there for four or five days with a full forensic team. It never came to anything.”
However, the story was not done there. For there were problems.
Doubts emerged about some of the evidence laid against Nat and, in May 2006, he was freed from Shotts Jail pending the outcome of an appeal.
Mr Smith said: “I was at the Tesco car park in Dingwall when I got the phone call to say he was getting out.
“I just sat there for an hour on my own and mulled over what the consequences were.
“I was utterly devastated – more so for Arlene’s family.
“I phoned the family and they were gutted like us.
“We had to endure the sight of Nat coming out of the prison full of the joys of spring.”
So what went wrong with the evidence?
There were two main problems: A set of Arlene’s rings went missing and reappeared without the defence being told, and the lip reader, Jessica Rees, became an unreliable witness because she admitted lying about her qualifications.
The missing rings
The two police officers who first attended Arlene’s house said they saw her three rings in the house.
We mentioned in part 1 of our series that a video police took of the house would later prove controversial.
The video showed no sign of those rings.
However, Arlene’s stepmother Catherine McInnes found these rings on May 7 – eight days after the video was filmed.
So the rings were in the house one day, then removed, then put back in the house.
But the Crown did not tell the defence about this, leaving Nat’s representatives handicapped.
Arlene’s best friend Michelle Scott said: “There’s only person who could have put it back there, because Nat was coming in and out of the house.”
We can today reveal what actually happened with the rings.
Mr Smith said Arlene’s family handed the rings on May 7 to a police officer.
He added: “The only problem with that is – the officer was also the guy who didn’t make the connection that the rings were relevant, and sat on them for about four days, with them in his desk drawer.
“Until he casually mentioned it one day in a briefing ‘oh by the way boss, the family handed me Arlene’s rings, they found them in the bathroom’ and I just about fell off my chair.
“He is a lovely guy (but) he didn’t quite see the investigative opportunity there.”
But finger-pointing began and police begin to clash with each other about who, if anyone, had messed up.
There was even a bizarre rumour that one officer who took his own life had been killed over the rings – a rumour that outraged his grieving friends.
Mr Smith said: “It’s classic conspiratorial c***.
“They hijacked his situation. That must have been distressing for his family.”
The second major issue about the evidence was Jessica Rees.
Her credibility was called into question by a 2005 episode of BBC2’s Newsnight and the English equivalent of the Crown Office said it would no longer use her as an expert witness.
She had lied on her CV about having a degree – something she later admitted.
We spoke to one retired police officer who questioned Rees’s involvement in the case.
The source said: “We were desperate for a conviction, but equally you have to give yourself a knock on the head sometimes – to say ‘that doesn’t seem credible’.
“There was never a high-five moment from her contribution.
“On one occasion, she mentioned something about a lock-up garage.
“We visited every lock-up garage in Elgin on the back of that and it led to nothing.”
Mr Smith did not comment about the merits of Rees’s intelligence, except to say it did turn some of Nat’s supporters against him.
He said: “She said Nat had made a comment related to disposing of human teeth.
“That quote was the stuff of nightmares. People who supported Nat started doubting him.”
Nat Fraser returns to Elgin
And that led to major rows when Nat was released from jail – with one incident in particular lighting the touchpaper.
Arlene’s best friend, Michelle Scott, said: “I just thought ‘oh my God, he’s back in Elgin.’
“Two or three times we were out in Elgin in the pubs and he would just wind you up, making comments.”
One night, Michelle and her pal Marion Taylor were in Dicey’s bar in Elgin.
Marion said: “I was actually up singing on the karaoke – with no idea Nat was in the bar.
“My friend came up and said ‘Nat is absolutely staring at you.’
“I finished my song. He was stood at the bar, sarcastically clapping away, smiling.
“He turned round and said to Michelle ‘where’s your pal tonight, then?’
“Then all hell broke loose. Michelle went to punch him. We all got chucked out.
“The security staff got them apart. Nat stood there and laughed at us.
“We called the police and they said ‘the best thing you can do is get on your way, he’s playing the big ‘I am’.”
Michelle added: “You just thought ‘how have you the gall to stand there and say that?
“‘There’s no need for you to say that.’
“We left and thought ‘that’s how it’s going to be. He’s going to lord it about Elgin’.”
Mr Smith said: “It was a difficult period. A website proclaiming Nat’s innocence sprang up.
“There was this juxtaposition where you were either pro-Nat or anti-Nat.
“For those who had spoken out against him – Nat’s got a long memory so there must have been a bit of unease for them.”
A menacing presence
Marion Taylor, Arlene’s close friend said: “It was as if the whole town was just watching you. I felt scared to be out.”
She alleges a man broke into Michelle Scott’s house with the intention to hurt her – but walked out when he saw Marion there.
“He walked in and made a beeline to Michelle’s bedroom. I was on the sofa. He looked at me, ran out and went away on a motorbike,” said Marion.
She added: “I’m convinced this was because Nat thought Michelle had to be ‘put in her place’. I told the police about it.”
The death of Glenn Lucas from a heart attack aged 55 in England in 2006 reopened old wounds.
Lucas had earlier co-written a book about the case, titled Murdered or Missing? which provoked anger from Arlene’s loved ones because it speculated that she could be still alive and living in Europe.
Asked for comment after Lucas’s death, Arlene’s father Hector McInnes said: “I would not wish anyone dead, but I don’t have any particularly strong feelings.
“He painted Arlene in a bad light in the book and said some unpleasant things about her just to sell a book.”
Things calmed down a little in December 2007 when Nat was returned to jail.
Several of his appeal bids failed and he stayed behind bars.
But in May 2011, five Supreme Court judges ruled Nat’s conviction unsafe due to the Crown not telling his defence team about the rings.
A retrial was announced – and the story was to enter its final phase.
We asked Nat Fraser and Hector Dick for comment and both declined.
Glenn Lucas has since died.
Read part 5 next
If you would like to speak to our Impact investigations team about the case, please email Dale.Haslam@eveningexpress.co.uk.