In a case that has horrified Britain and exposed the darkest corners of teenage online obsession, 18-year-old Tristan Roberts meticulously documented his own mother’s brutal murder over more than four agonising hours — recording every blow as he smashed her skull with a hammer in a cold, calculated execution inspired by his twisted fixation on fictional serial killers.

The victim: Angela Shellis, a 45-year-old devoted teaching assistant and loving mother from Prestatyn, North Wales, who had spent years trying to get help for her troubled son. Instead of gratitude, she received betrayal of the most monstrous kind — lured from her own home under the false promise of medical help, led to a secluded nature reserve, and bludgeoned to death in the early hours of October 24, 2025, just ten days after her son turned 18.

Roberts, from Coniston Drive in Prestatyn, didn’t just kill his mother. He turned the atrocity into his own personal horror movie, narrating the attack on a dictaphone while boasting online like a deranged anti-hero. Before the murder, he flooded Discord and other platforms with disturbing messages announcing his plans, comparing himself to the TV serial killer Dexter and the psychotic Patrick Bateman from American Psycho. He openly expressed misogynistic hatred toward women and researched weapons using an AI chatbot, which reportedly guided him toward using a hammer.

The chilling voice recording began with the words that still send shivers down the spine: “This is Tristan Roberts. Tonight I’m going to be Alex and I’m going to murder my mother with a sledgehammer.”

What followed was more than four hours of pure evil captured in audio — starting with an initial violent assault inside the family home where he held Angela hostage in her bedroom, inflicting bruises to her face and strangulation injuries. She begged him to let her call 999 for help. He agreed to take her “into town” for medical treatment — but it was all a deadly lie.

CCTV footage, described in court as harrowing, captured the final walk of Angela Shellis. Roberts, wearing a backpack containing the fatal hammer, led his mother by the arm through the streets in the dead of night. He even made her wear a balaclava. The pair crossed a railway line before reaching the isolated Coed y Morfa nature reserve. There, he ordered her to sit on a bench. Moments later, screams echoed as he pulled out the hammer and rained down at least four heavy, sickening blows to her head. After the first strikes, Angela was heard no more.

Roberts didn’t stop there. He continued the frenzied attack, documenting every detail as if performing for an invisible audience of fellow dark-web enthusiasts. After the killing, he dumped her body in undergrowth and casually posted on Discord: “I’ve just had the craziest day… beat the s*** out of her… smashed her skull in so hard with a sledgehammer.”

The sheer premeditation shocked even hardened investigators. Roberts had spent at least three weeks planning the murder. He waited until he legally turned 18 to buy multiple hammers, knives and axes. He changed his Discord status to “tonight’s the night.” He consulted AI for advice on the best weapon. And throughout, he immersed himself in violent fictional worlds, blurring the line between fantasy and the real-life horror he was about to unleash on the woman who had raised him.

Angela Shellis was no stranger to struggle. As a single mother and teaching assistant, she had tried desperately to support her son and get him professional help amid his growing obsession with violence and misogyny. Instead, her love was repaid with calculated betrayal. Court heard she had been held prisoner in her own bedroom for hours before the final deadly journey to the nature reserve.

On March 25, 2026, at Mold Crown Court, Tristan Roberts was sentenced to life imprisonment with a minimum term of 22 years and six months for the murder. The judge described the killing as premeditated and brutal, noting the disturbing recordings and online boasts. The voice recording was deemed so harrowing that it was not played in open court.

The case has sent shockwaves through North Wales and beyond. Prestatyn, a quiet coastal town, now grapples with the knowledge that such evil could fester behind the doors of an ordinary family home. Neighbours and colleagues of Angela have spoken of a kind, dedicated woman who always put others first — especially her son.

The wider implications are chilling. Roberts’ deep immersion in fictional serial killer culture — Dexter’s “code,” Bateman’s cold detachment — raises urgent questions about how online content, combined with easy access to AI tools and weapons, can radicalise vulnerable young minds toward real-world violence. His misogynistic rants and open planning on social platforms went unchecked until it was far too late.

For Angela’s family and friends, the pain is immeasurable. A devoted mother who worked with children every day had her life violently ended by the child she tried hardest to save. The nature reserve where her body was found, once a peaceful green space, now carries the stain of unimaginable betrayal.

Police launched an immediate investigation after the body was discovered. Roberts was quickly arrested and charged. Evidence including the dictaphone recording, multiple weapons at the home, DNA on the hammer, and his own online posts left little room for doubt. The premeditation was overwhelming.

In the weeks leading up to the attack, Roberts had grown increasingly isolated and fixated. He researched killing methods, acquired tools, and rehearsed his dark fantasies. Angela, sensing danger, had pleaded for help — but her son’s obsession had already consumed him.

The sentencing brought a measure of justice, but no sentence can undo the horror of a son luring his own mother to her death under the guise of care, then recording the savage hammer blows as if it were entertainment.

This was not a crime of passion or momentary rage. It was a cold, scripted execution by a teenager who saw himself as the protagonist in his own twisted serial killer story — inspired by television and movies, enabled by technology, and carried out against the one person who should have been safest.

As details of the four-hour recording and Roberts’ boasts continue to emerge, the public is left asking how a young man could descend so far into darkness while living under the same roof as his victim. How many warning signs were missed? How much influence do violent fictional characters truly exert on impressionable minds already struggling with hatred and isolation?

Angela Shellis deserved better than to die at the hands of the son she loved. She deserved protection, not betrayal. Her final moments — led through the night, forced to wear a balaclava, sitting on a bench in a dark reserve before the hammer fell — represent every parent’s worst nightmare.

Tristan Roberts now faces decades behind bars, but the shadow of his crime will linger far longer. In Prestatyn and across the UK, families are hugging their children tighter tonight, while authorities and online platforms face renewed scrutiny over how to spot and stop the next “Dexter” wannabe before fantasy turns fatal.

The hammer has fallen silent. The dictaphone recording has been secured as evidence. But the screams captured in those four hours — and the final, desperate cries of a mother begging for her life — will echo in the memory of everyone who has followed this heartbreaking case.

A loving teaching assistant gone. A quiet town scarred. And a teenager who chose the path of fictional monsters over the real woman who brought him into the world.

This is the true face of obsession unchecked — and it is more terrifying than any TV serial killer could ever be.