Content warning: This article contains graphic details of violence and assault.

With over 30,000 subscribers on YouTube, Stephen McCullagh made a living by live-streaming video games online.

On December 18, 2022, people tuned in to watch a six-hour stream of Stephen playing Grand Theft Auto (GTA) at home.

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"I am not leaving the house tonight," he said in the livestream, according to The Guardian.

His audience had no idea the stream was staged.

As the video played out, McCullagh's partner, Natalie McNally, was brutally murdered in her home in Lurgan, Northern Ireland — just 27 kilometres away.

The 32-year-old was 15 weeks pregnant with a baby boy.

The murder of Natalie McNally.

Natalie had only been dating McCullagh for a few months when she found out she was pregnant with his child.

The couple had met on the dating app Bumble, and after a few dates, the relationship moved quickly, RTE reports.

When she told McCullagh she was pregnant, he was thrilled. They started affectionately referring to the baby as "Baby Squish" and planned to move in together to prepare for the birth.

But three months into her pregnancy, McCullagh arrived, uninvited to Natalie's house, disguised in gloves.

He beat, strangled and stabbed his partner to death, while his livestream, which appeared to show him at home gaming, played out online.

As it was only a few days before Christmas, he was wearing a Santa hat in the stream, drinking Guinness and eating snacks as he played GTA and Robot Wars.

The video had been recorded four days earlier, according to The Irish Times.

Before leaving her body, McCullagh placed Natalie's head face down in a dog bowl, in what a judge described as "part of her punishment and humiliation", The Irish Times reports.

After the murder, McCullagh changed his clothes and caught a taxi back home, before returning to Natalie's house the following evening. There, he called the authorities to alert them that he had found a body.

"Here, and for the weeks that followed, he masqueraded as a distraught and caring partner," Detective Chief Inspector Neil McGuinness said in a statement.

The investigation and trial.

Once Natalie's body was found, an investigation ensued.

When questioned, McCullagh initially tried to point the finger at Natalie's ex-boyfriend.

During the police investigation, authorities conducted house-to-house inquiries and found thousands of hours of CCTV footage, documenting McCullagh's journey to Natalie's house, according to a police statement.

"This was not a spontaneous murder but a planned-out one," Justice Patrick Kinney said during the trial that began earlier in 2026.

"The defendant did not just kill Natalie McNally. Her unborn child also died as a result of the murderous assault.... he knew that her baby at such an early stage of pregnancy would have no chance of surviving the attack," Justice Kinney said.

Speaking directly to McCullagh, he said: "You planned this murder in remorseless detail. You attacked someone you profess to love in a frenzied assault, which was characterised by its excessive and gratuitous violence. Despite that frenzy, the killing was cold-blooded and calculated."

The reason behind the brutal attack remains unclear three years later. However, the prosecution's case against McCullagh suggested he read messages from Natalie to other men in the weeks before her death. According to the BBC, some of these messages implied breaking up with McCullagh, whilst others were sexually explicit.

At the trial, Public Prosecution Service assistant director Catherine Kierans said, per The Guardian: "I've never seen a case like this in terms of domestic murder with such a level of premeditation, planning, thinking of every possible aspect — the wearing of a disguise, the forensic awareness, the framing of the ex-partner."

On June 3, after the jury had unanimously found McCullagh guilty of Natalie's murder, he was sentenced to 31 years in prison.

Remembering a 'loving and independent young woman.'

As he sentenced McCullagh, Justice Kinney described Natalie as "a strong, loving and independent young woman," The Irish Times reports.

"She knew what she wanted from life and was intelligent, passionate and funny."

After the trial was finally complete, Natalie's father, Noel McNally, spoke out, holding a picture of Natalie.

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"Today is not a celebration of the sentence handed down, as Bernadette, my boys and myself are serving a life sentence since the murder of our beloved Natalie," he said, The Guardian reports.

"But hopefully it will serve as a deterrent to help stop violence against women and girls in this country."

If you or anyone you know needs to speak with an expert, please contact 1800 RESPECT (1800 737 732) — the National Sexual Assault, Domestic and Family Violence Counselling Service. If you are in immediate danger, call 000.

RizeUp Australia is Mamamia's chosen charity partner, a nation-wide organisation that walks with victim-survivors of domestic and family violence to deliver practical, life-changing support. RizeUp supports women and families as they rebuild safety and stability after violence. Donate here to create safe homes and new beginnings.

Feature image: Supplied.