In the early hours of 24 October 2025, the quiet family home on Coniston Drive in Prestatyn, North Wales, became the scene of unimaginable terror. For nearly four hours, 18-year-old Tristan Roberts held his 45-year-old mother, Angela Shellis, prisoner in her own bedroom. Armed with a hammer he had recently purchased online, he struck and strangled her while she remained conscious, repeatedly begging him to call 999 and pleading for her life. Despite her desperate cries, Roberts ignored every plea. Eventually, he deceived her into leaving the house, convincing her he would take her for medical help. Wearing a balaclava or mask over her head “for protection,” the respected teaching assistant walked beside her son into the darkness, unaware that he was leading her to an isolated footpath near the Coed y Morfa nature reserve, where he would bludgeon her to death with the same hammer.

Angela Shellis was remembered by colleagues at Rhyl High School and the wider Prestatyn community as a caring, hardworking mother who never gave up on her children, no matter how difficult life became. She had been trying to get help for Tristan, who had been diagnosed with ADHD and autism and whose behaviour had grown increasingly disturbing in the months leading up to the attack. Her older son, Ethan Roberts, had also been deeply worried about the potential danger his younger brother posed to their mother. In a moving victim personal statement read in court, Ethan expressed overwhelming guilt, anger, grief, and depression, revealing that he had sensed something was terribly wrong when he tried to contact his mother that morning. “All my mum ever did was love Tristan,” he said. “She’s the only person who’s done anything and everything for him. She tried to get help for him, and fought for him, but he never accepted.”

The horror began late on the evening of 23 October 2025 — just ten days after Tristan turned 18. He had spent weeks meticulously planning the attack, researching methods online, purchasing weapons including knives, hammers, axes, and protective gloves as soon as he was legally old enough, and posting chilling messages on the Discord platform under multiple aliases. In one post, he declared: “This is Tristan Roberts. Tonight I’m going to murder my mother with a sledgehammer.” He referenced the film American Psycho, sharing violent fantasies and bragging about the control he would exert over his “terrified” mother. He even recorded voice notes outlining his intentions and admitted in one message that standing over her with the hammer while she slept had nearly traumatised him.

Disturbingly, Tristan had also consulted an AI chatbot for advice on weapons and cleaning bloodstains, bypassing safety filters by claiming he was writing a book about serial killers. These interactions, uncovered during the police investigation, have highlighted growing concerns about the risks of unregulated artificial intelligence providing guidance on violence.

Inside the family home that night, Tristan began his assault around 11 p.m. He kept Angela confined to her bedroom, brandishing the hammer and inflicting bruising to her face and strangulation injuries while she remained fully aware and pleading for help. For almost four agonising hours, she begged him to stop and call emergency services. The attack was captured on a voice recording lasting several hours — a “trophy” that Tristan narrated himself, at one point speaking in an American accent as he described his actions. Prosecutors later described the audio as so harrowing that the judge chose not to play it in full during the sentencing hearing.

Eventually, Tristan convinced his injured mother to leave the house, telling her he would take her into town for medical assistance. CCTV and doorbell footage captured the heartbreaking moment at around 3:19 a.m. when Angela, limping and using a crutch due to a recent knee injury, walked beside her son. She had a balaclava or mask over her head as they left their home on Coniston Drive. The pair crossed a railway line and made their way to a footpath beside the Morfa nature reserve. Once they reached an isolated spot, Tristan instructed her to sit on a bench. He then took the 4lb hammer from his rucksack and struck her multiple times to the back of the head — at least four devastating blows that caused catastrophic injuries. He continued recording the fatal assault on the dictaphone.

After the murder, Tristan dragged his mother’s body around 100 metres into the undergrowth, where it was discovered the following morning, 24 October 2025, by a dog walker around 8:30 a.m. In the immediate aftermath, he used Angela’s mobile phone to reply to messages from his brother Ethan, pretending she was asleep in bed. He continued posting online, boasting about the crime under different identities.

North Wales Police quickly identified Tristan as the suspect through his extensive online activity, the weapons purchases, and the voice recordings. He was arrested at the family home later that day and charged with murder after a series of interviews in which he answered “no comment.” At Mold Crown Court, he pleaded guilty to murder in February 2026. On 25 March 2026, Judge Rhys Rowlands sentenced him to life imprisonment with a minimum term of 22 years and six months before he can be considered for parole. The judge described the premeditated and callous nature of the crime, noting how Tristan had revelled in the control he exerted over his own mother.

Ethan Roberts’ statement in court revealed the profound trauma inflicted on the entire family. He described the overwhelming guilt and questions that haunt him daily, the stress that forced him to temporarily withdraw from university, and the disbelief that his brother could commit such an act. Angela’s sister, Sarah Gunther, paid tribute to her as a “fantastic and fiercely supportive mum” who never gave up, no matter how hard life became. The family’s victim impact statements painted a picture of a devoted mother who had done everything possible to help her son, only to become the target of his deep-seated hatred and violent fantasies.

This case has sent shockwaves through the Prestatyn community, where Angela was well-known and respected as a teaching assistant who dedicated herself to helping young people. Her murder by the son she had fought so hard to support has left deep emotional scars. It has also sparked urgent conversations about online radicalisation, misogynistic extremism in gaming and chat platforms like Discord, mental health support for families, and the dangers of artificial intelligence providing advice on harmful topics.

Tristan’s immersion in violent online content, his obsession with serial killers and horror films, and his ability to plan such a calculated attack while living at home have exposed gaps in early intervention. Angela had tried to seek professional help for her son as his behaviour deteriorated, but like many families facing similar challenges, she encountered difficulties accessing timely and effective support.

The haunting CCTV images of Angela walking beside her son in the dead of night — trusting him even after hours of violence — have haunted many who followed the case. Her final hours, from the desperate pleas ignored in her bedroom to the midnight journey that ended in betrayal and death, reveal a profound and heartbreaking failure of protection.

As Tristan Roberts begins his life sentence, the family he devastated must somehow find a way to live with the unimaginable pain. Ethan’s words echo the sorrow of many: a mother who only ever showed love, now gone at the hands of the son she never stopped trying to help. Angela Shellis’s story stands as a tragic reminder of the hidden dangers that can lurk within families, amplified by toxic online spaces and unchecked fantasies.

In the wake of the sentencing, there have been renewed calls for better mental health resources, stricter oversight of online platforms that host extremist or violent content, and safeguards to prevent AI tools from enabling harm. For the people of Prestatyn and beyond, this case will long be remembered not only for its brutality but for the courage of a mother who fought for her son until the very end, and the devastating consequences when that love was met with hatred.