The hundreds of texts at the centre of Graham Dwyer's Supreme Court appeal show how he manipulated a troubled woman by feeding on her insecurity and helplessness
Graham Dwyer's trial for the murder of Elaine O'Hara stands out in the history of our criminal justice system as probably the most harrowing and grotesque drama ever to unfold in an Irish courtroom.
In the words of Seán Guerin SC, who prosecuted the case against Dwyer, it was "almost the perfect murder" and she was "almost the perfect victim".
And were it not for an extraordinary series of coincidences involving a long hot summer, a curious angler, an inquisitive dog and a diligent garda we would never have known about the monster that lay hidden in what Elaine O'Hara's father described as Dwyer's "depraved and diseased mind".
Analysis of how Dwyer manipulated, exploited and groomed his victim for murder exhibits the classic characteristics of a serial killer, yet all the evidence shows that Ms O'Hara was his first victim.
Guilty: Graham Dwyer murdered childcare worker Elaine O'Hara in 2012. Photo: Collins
However, had he managed to get away with his horrific crime there is every good reason to believe that he would have killed again. Gardaí conducted exhaustive enquiries both here and abroad and were satisfied that this was his first murder.
To the casual observer Dwyer was the quintessential Mr Average: a successful architect and family man who lived a comfortable life in upmarket suburbia.
He was like the proverbial twig in the forest.
But on the other side of his dual existence, and well hidden from view, was a cold-blooded predator who his 'slave' - Ms O'Hara - called the 'Master'.
Ms O'Hara was ideal for his nefarious purpose: a vulnerable, fragile woman who had been blighted by depression, anxiety and a chronic lack of self-esteem since childhood.
Her mental health issues first manifested as self-harm, which escalated to a number of suicide attempts followed by long periods in a psychiatric hospital.
The absent sense of self-worth and a personality disorder were reflected in her interpersonal relationships which made her socially withdrawn and untrusting: she had few close friends and no boyfriends. She tended to keep her worried family at a distance.
Her medical records noted that she was "sad and angry" and finding it "difficult to control her impulses". When she was 24 she was diagnosed with "recurrent depressive disorder with a strong possibility of emotionally unstable personality disorder".
Her grim situation was compounded by asthma and diabetes and the fact that she smoked heavily. Dyslexia, which affected her writing and verbal abilities, added to her sense of insecurity and low self-esteem.
Life had dealt Ms O'Hara a raw deal.
Somewhere along the way she was drawn into the twilight world of sexual fetishism. Her sexual preference was for restraint; being dominated, tied up, controlled and punished.
The troubled woman joined BDSM websites where she interacted with others who were interested in bondage and domination. That was where Dwyer found her around 2008.
On her profile Ms O'Hara said she wanted someone who could train her "to be the best submissive slave" she could be. And there the dysfunctional relationship began.
Dwyer took full advantage of her willingness to serve him. Like a parasite he nourished himself feeding on her insecurity and helplessness. He played with her like a cat with a mouse.
Dwyer's predilection was more extreme than BDSM - he derived sexual gratification by stabbing a woman during sex and drawing blood.
Psychologists refer to it as "piquerism", which was defined by one academic at Nottingham Trent University as "paraphilic sexual arousal which hinges on the sadistic piercing and stabbing of another person, especially in the breast, buttocks and groin which may cause enough bleeding to be fatal".
A paraphilic disorder is a sexual desire to cause an unwilling victim psychological distress, injury or death. The distinctive signature of the murders carried out by Jack the Ripper involved piquerism.
Dwyer's macabre perversions first emerged in his late teens.
A girlfriend recalled how he told her his fantasy was to stab a woman during sex. During their relationship he brought a kitchen knife into the bed, which he found arousing, and then pretended to carry out his frightening fantasy on her.
But somehow he managed to contain his pernicious side behind a wall of strict secrecy where only his slave was allowed access.
He hid all trace of his other self from closest friends and family, including his wife and mother of their two children.
She only discovered his monstrous secret on the morning that gardaí arrived at their home in the Dublin suburb of Foxrock to arrest her husband of 15 years.
When Ms O'Hara disappeared on August 22, 2012 it was the culmination of several months of careful planning by Dwyer.
Earlier that day she had discharged herself from a psychiatric hospital where she had been a regular patient, and the indicators were that she had turned the corner in her struggle with depression.
She had planned to work as a volunteer at the Tall Ships Festival in Dublin the following day, news that was greeted as a very encouraging development by her loving family and therapists. One of them described how she "almost seemed happy" for the first time.
Ms O'Hara was also hoping to complete her studies as a Montessori teacher.
But behind the scenes Dwyer, the master, was in full control of his 'slave' and the hundreds of texts that were at the centre of his Supreme Court appeal provided the script for this horrific story.
When she was last seen alive Ms O'Hara was walking towards the seashore beside Shanganagh Park in Shankhill in south-east Co Dublin.
She had parked her car nearby and left her precious iPhone, cigarettes and inhaler behind, things that she carried everywhere.
Inevitably, Ms O'Hara's long history of mental health problems worked in Dwyer's favour, as the gardaí and her family began to believe that despite the signs of hope she had finally succumbed to the suicide ideation which had haunted her sad life.
But then a year later, in the late summer of 2013, coincidence and fate colluded to expose the shocking truth.
A dog being walked in the Killakee woods in the Dublin Mountains led his owner to the skeletal remains of Elaine O'Hara.
At the same time an angler who was looking into Vartry Reservoir, which had dropped to just a few feet deep following the summer heat wave, noticed shiny objects that turned out to be BDSM paraphernalia dumped by Dwyer after he had murdered his slave.
The fisherman brought the strange items to a local garda in Roundwood station, who kept going back to the spot until he found Ms O'Hara's keys - at the same time that a pathologist confirmed that the remains found in the mountains were those of a missing woman called Elaine O'Hara.
Further searches by gardaí located two discarded telephones and when they were analysed hundreds of vile, disgusting texts were retrieved which in turn identified the author.
