Diary of a killer: How primary school teacher used an alter-ego to plot her partner's murder

• Rebecca Haworth examines how Fiona Beal was brought to justice

A week into her retrial at the Old Bailey, school teacher Fiona Beal changed her plea to admit the murder of her ex-partner Nicholas Billingham. At the heart of the prosecution case was evidence Beal had written in her own diary, using the alter-ego Tulip22, which charted her progression from respected primary school teacher to a killer in cold blood.

After Fiona Beal plunged a knife into the neck of her partner, and left him to bleed to death in their bed, she returned to her diary.

"It was harder than I thought it would be," she wrote.

"Hiding a body was bad. Moving a body is much more difficult than it looks on TV."

She had buried Nicholas Billingham, 42, in the garden of the bay-fronted terraced house they shared in Moore Street in Northampton.

By the time his body was found in March 2022 - four and a half months after he was last seen - his remains were said to be partly mummified.

From the outset of the trial - a retrial after the first collapsed for legal reasons - there was never any doubt that Beal, 50, had killed Mr Billingham.

She had admitted as much during the first trial, when her own defence barrister Andrew Wheeler KC if she accepted that she killed him.

She told Northampton Crown Court: "Yes, I accept that. I don't remember a lot of detail, don't remember much at all about when it actually happened or the months afterwards."

At the second trial, at the Old Bailey in London, the Eastfield Academy teacher admitted manslaughter but had denied murder, until she changed her plea midway through to admit murder.

That guilty plea brings to a conclusion a case that dates to November 2021, when Mr Billingham's body was found, and includes the first trial which was abandoned in June last year, after 17 weeks of evidence had been heard.

That included excerpts from her diary read to the court which painted a picture, not only of what happened that night, but of the state of mind of a woman who turned into a killer.

Beal - described by educational colleagues as a "high-functioning professional" - had written about an alter-ego she said emerged when she smoked cannabis.

"I thought about leaving him [Mr Billingham], but the things he said and did fuelled my dark side," she wrote.

"I call her Tulip22. She’s reckless, fearless and efficient. Ruthless.

"I started plotting as Tulip22 after he’d gone to bed."

In another entry, she wrote about the night she murdered him, which the prosecution say happened between 31 October and 10 November 2021.

"While he was in the bath, I kept the knife in my dressing gown pocket and then hid it in the drawer next to the bed. "I brought a chisel, bin bag and cable ties up too. I got him to wear an eye mask."

Beal had told the earlier trial that when the two met in 2004, he had appeared charming, but over time, he became more and more abusive - making comments about her appearance, her cooking and housekeeping.

The jury were told that Mr Billingham, who was a self employed builder, had affairs during their 17-year relationship and had fathered a child with another woman.

They also heard that he had lost thousands of pounds gambling.

In court, Beal's barrister said: "He was psychologically domineering, and over the years wore her down until she was quite literally broken."

In her diary, she wrote: "Seventeen years of him being argumentative, mean, cruel, belittling, nasty, lying, cheating, gambling, narcissistic, controlling.

"Emotionally abusive, controlling, verbally abusive, sexually demeaning."

In the weeks that followed Beal tried to hide what she had done.

She used Mr Billingham’s mobile phone to text his family, friends and work colleagues as if he were still alive, and had left her.

But her efforts to cover up his disappearance fell apart in March 2022.

She was reported missing by Eastfield's headteacher after she failed to return to work.

The police traced her to a holiday home site near the town of Windermere in Cumbria called High Borrans Lodges, where she had booked a cabin for 10 days.

They found that she had tried to take her own life. Officers also discovered notebooks in which Beal had written what amounted to a confession.

That prompted them to search their home and they found Mr Billingham’s body, buried in that back garden.

The prosecution said it was a murder she had planned.

The court was shown CCTV footage, that shows her visiting the B&Q store just days after it happened, buying compost, bark, decorative stones and other items that she used to cover the area in their garden where she’d buried him.

She had wrapped his body in black plastic and cable ties.

A post-mortem examination revealed the knife had severed his right jugular vein.

Reflecting on those events in her diary, she wrote: "I started to believe the cover story.

"Flashes interrupted. But in the dark times or just at random moments I would remember.

"Remember what I’ve done. What I am.”

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