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The secret life of driller killer Colin Howell, his mistress and their murder plot – part one

This is the story of how the couple plotted the deaths of their respective partners and how a crisis of conscience finally brought the crime to light.

Colin Howelll

Colin Howell hid his relationship with Hazel from his wife Lesley

Hazel Buchanan

Colin and Lesley after their honeymoon

Hazel and Trevor Buchanan were married in 1981

Sunday World

COLIN Howell and Hazel Stewart’s forbidden love drove them to commit the near-perfect crime.

To onlookers they were the epitome of respectability – he the successful dentist with a flourishing practice that afforded him a life of luxury, she the glamorous wife of a retired high ranking police officer, regular church goer, pillar of society.

To all intents and purposes they were the most unlikely of killers but they went about their daily lives for 19 years hiding the terrible truth of their former lives as illicit lovers, and how that love drove them to the ultimate act – murder.

This is the story of how the couple plotted the deaths of their respective partners and how a crisis of conscience finally brought the crime to light.

THE BEGINNING – spring 1990

COLIN HOWELL held his three year-old daughter’s hand as he led her towards her classroom at the Mountsandel Nursery School in Coleraine.

His mind was elsewhere as they approached the door — his dental practice in Ballymoney, Co Antrim, wasn’t doing as well as he had hoped and the renovations in the new family home in Knocklayde Park were dragging on.

A friendly voice from the classroom snapped him back to reality, and when he glanced up at the pretty blonde nursery assistant he couldn’t help but smile back at her.

He knew he shouldn’t be thinking about another woman, especially after his wife had caught him having an affair a few months prior, but there was something about Hazel Buchanan, an RUC constable’s wife, that he had first noticed when he met her gaze at the church they both attended.

He knew he would see her again soon — if there was one certainty in his life it’s that he would not miss Sunday service.


Hazel Buchanan had felt as though she was stifled at home with the children, but a part-time job as an assistant at Mountsandel Nursery in Coleraine gave her a new lease of life.

Her husband Trevor Buchanan was unimpressed by his wife’s change in attitude, and arguments became more frequent.

Although he adored his wife, Trevor’s work as a police officer kept him away from home for long shifts, and Hazel found herself looking forward to brief conversations with Colin Howell at the school gates, at the church playgroup and during swimming lessons.

His wife Lesley was pregnant with their fourth child, so Colin joined the children at the swimming pool. While the kids were splashing about in the shallows, Colin and Hazel got closer in the deep end.

Hazel Buchanan

With his hands supporting her body as she practised the front crawl, Colin confessed: “I’m not having innocent thoughts about you, Hazel.”

Unfazed by his disclosure, Hazel replied: “Well, I’m not that innocent myself...”


After they had sex for the first time, Hazel seemed conflicted.

She questioned what had just happened as she lay on her marital bed with someone else’s husband, and Colin was quick to retort: “We just had sex, do you want me to explain it to you?”

Despite Hazel’s conflict, the sexual relationship continued throughout the summer of 1990.

They would regularly meet at Castleroe Forest Park to have sex, and in August, Hazel discovered she was pregnant.

Colin told her not to worry, he had been through it before with Lesley before they were married; he knew where they could go to deal with the issue, which was a baby fathered by either Hazel’s dark-haired husband, or the fair haired dentist she had been sleeping with.

All they had to do was excuse themselves for a night away in London so Hazel could have the abortion at a clinic. Trevor rarely questioned Hazel any more — the constant arguments were draining him — so he wasn’t entirely surprised when he found a note from her that read: “Going through a really hard time. Don’t worry about me, don’t try to find me, I’ll be back in a few days. Love you”.

When Hazel arrived home the following night he was glad to see her, and she was relieved she had got away with it.

The affair is discovered

The following month, Hazel and Colin were spotted by a member of the Coleraine Baptist Church parked beside each other in Castleroe Forest Park, and word soon reached Pastor John Hansford.

The pastor had already heard from Lesley, who had recently given birth to the couple’s fourth child, and was starting to have suspicions about the time her husband was spending with Hazel Buchanan.

The pastor made his way to Colin’s dental practice in Ballymoney. It was a busy surgery and it seemed to be doing well as it was decked out with state-of-the-art equipment and new examination chairs.

Colin invited him into an empty room after being assured the conversation would not take long.

Pastor Hansford was direct when he asked Colin if he was having another affair, but Colin seemed stunned by the accusation and adamantly denied that he was cheating on his wife.

The pastor left the dentist’s surgery unconvinced, and he went to Hazel Buchanan’s house to ask her if something was going on between her and Colin.

Colin and Lesley after their honeymoon

Pastor Hansford later recalled the initial interaction: “She mentioned that Trevor was an ordinary guy and reflected on her own childhood and upbringing, which she said was restrictive. She said that she wished Trevor was more of an exciting husband.

But I told her he was a really good guy. I would often see him around the place on duty, talking to the public and doing what was a first-rate job protecting the country.

“I told her he may not be the exciting husband she wanted but in terms of faithfulness he was not to be despised, but cherished.”

But while driving the pastor home, she finally broke down in tears and told him that an emotional affair had just begun, but she adamantly denied that it had been physical.

The pastor drove to the Howells’ house where Lesley was at home with the children.

He prepared her before Colin arrived back from work and was confronted with his lies.

Colin was devastated and repentant before his wife and the pastor.

Broken marriages

Lesley consoled herself by going for sunbed sessions, dyeing her hair, dieting and going to an aerobics class with her friend. It was at one of these classes that Lesley told her friend that Colin had been giving her some tablets.

“She said she was fine, he was looking after her,” her friend later recalled.

Colin busied himself with the church as he scrambled to return to his respected position within the inner circle.

Lesley and Trevor found comfort in each other. While Hazel and Colin were abiding by the church-imposed restrictions on their communication, the scorned spouses tried to console one another.

The couples continued to go to counselling sessions with Pastor Hansford, and they spoke about their relationships and the things they felt contributed to the problems.

Lesley and Trevor both felt as though they had not been good enough spouses. At the start of 1991, just four months after the affair was revealed, Colin offered to meet with Trevor in front of the pastor, to apologise face to face.

Trevor had never been bitter towards Colin, he felt as though he could never measure up. In fact, Trevor had been so non-confrontational that he had waved Colin on at a police checkpoint on one occasion so he did not have to speak to him.

After a half an hour discussion, Colin apologised to Trevor and begged for his forgiveness.

Trevor accepted the apology and even shook Colin’s hand.

The counselling sessions seemed to be a success, and Pastor Hansford left to go to India for six weeks, feeling confident that the healing process was well and truly underway.

Before he left he told Colin: “Hazel is doing well, she’s moved on, and so should you.”

Colin just had to know for himself though, so in March, he dialled her number, and when she picked up he described it as being like: “Holding your breath, and when Hazel was glad to hear from me it was like coming up for air, the wrong sort of air.” Hazel told him: “I will love you until I’m old and grey”

The affair began again.

Lesley falls apart

Colin was able to sneak out of the house while Lesley slept because he had given her tranquillisers that she washed down with glasses of red wine.

He was able to cycle or jog through the woods by Mountsandal and enter Hazel’s garden through the back gate.

With Trevor working nights, they knew they would be undisturbed.

Trevor seemed to be in a better place, he downplayed the affair in conversations and said that he wasn’t perfect either, but he was glad to be back in the marital bed.

By April, Lesley had tried to forgive Colin, but she could not forget, and every time he left the house she believed he was meeting Hazel.

Colin later said: “A confrontation developed over me being late back and it continued. There was an iciness in the house and Lesley put on her dressing gown to get ready for a bath.


“Lesley carried the cassette player into the bathroom to listen to music as she tried to relax. She was beginning to connect the plug at the top end of the bath and I said she better not set it there because it could fall in.

“At one point I sat on the edge of the bath.

“It was a dark moment and she wouldn’t let go of the argument that I had contacted Hazel. A thought went through my head, ‘I want you to shut up, and I thought if I threw it in I would kill you’, although I’d no intention of doing that.

“I showed Lesley the plug. I was in control.

“And with the unsecured loop of the cable I flicked it across her back, then dropped the plug on the floor where it made a noise.

“Lesley looked at me, there was a pregnant pause and a shift of power. I was about to take power and I wanted her to realise that. I flicked the cable and walked out of the door.”

Lesley remembered the incident differently and she called a friend to discuss it, saying: “I’m telling you this in case anything happens to me.”


Colin Howell had grown up in Belfast, the second youngest of five children, in a deeply religious family.

As soon as he and his wife of seven years, Lesley, had moved to Coleraine just after the birth of their first child in 1984, they had joined Coleraine Baptist Church and it didn’t take long for Colin to become a pillar of the church community.

Colin met Lesley Clarke in 1981 while they were at Queen’s University in Belfast.

He was studying dentistry and Lesley was on her way to becoming a nurse, where she would thrive on the wards of the Royal Victoria Hospital in Belfast.

They were married within two years, and as Colin made his way up the career ladder, Lesley resigned herself to staying at home to raise the three children they’d had at two-year intervals since.

Colin’s affair with an old classmate from university in late 1989 had knocked Lesley’s confidence, and despite his repentance, she wondered if she could ever trust him again.

It wasn’t as if he had not cherry-picked what Bible scriptures to follow before, when they had premarital sex and three subsequent abortions in England.

The only thing stronger than Colin’s religious convictions was his sexual appetite, but he felt as though he would be forgiven for his perceived sins if he just confessed to his pastor, time and time again.

Hazel and Trevor Buchanan were married in 1981


Hazel Elkin was raised on a farm just outside Omagh with nine siblings.

Her parents were members of the Baptist congregation and the family spent as much time at the church as they could when they weren’t tending to the dairy farm.

Hazel longed for a life away from the farm, and when she was 18 she met 22-year-old Trevor Buchanan, a Royal Ulster Constabulary hopeful. He came from a family of RUC officers — three of his five brothers were serving members and as the youngest boy, Trevor looked up to his siblings in uniform.

The couple were married in 1981 at Hazel’s church and although Trevor wasn’t as devoutly Baptist as his wife, he was willing to join the flock.

Hazel was seen to be a positive influence on Trevor — he didn’t go out drinking with his colleagues as much, he quit smoking and he tried hard to give his family everything they could want.

But sometimes it seemed as though it was never enough for Hazel.

By the time they moved to Charnwood Park in Coleraine in 1986, the Buchanans had two children, a five-year-old girl and a four-year-old boy. The young family fitted right in at the Baptist church, and within a few years their lives would collide with the Howells — with devastating results.

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