In the quiet cul-de-sac that he called home, the comings and goings of Dr Thomas Kwan raised no suspicions.
And why would they? Middle-aged and married with a young son, the 53-year-old GP was the very picture of respectability.
But what we now know is that Kwan was hiding a deadly secret.
And the key to that secret was to be found in the detached, red brick garage beside his £400,000 house.
Inside was an array of deadly chemicals including liquid mercury, thallium, sulphuric acid and arsenic. Also stored there was a container full of castor oil beans along with a recipe for how to turn the beans into ricin.
Ricin is a deadly poison, for which is there is no known antidote. Just a few micrograms is sufficient to kill.
The toxin famously featured in Breaking Bad, the American crime drama about an unremarkable chemistry teacher called Walter White who turns to crime to solve his financial problems.
Unsuspected by all, he uses his knowledge to make and sell methamphetamine. As his life spirals out of control, he produces a batch of ricin to poison a rival drug dealer.
Kwans descent from medical practitioner to master poisoner was no less remarkable.
And, like Walter White, his motivation was money.
Thomas Kwan, 53, admitted trying to murder Patrick OHara at the home he shared with the doctors mother in Newcastle
Kwans mother, Wai King - also known as Jenny Leung - is pictured outside court during an earlier hearing
Patrick OHara (pictured) was given a poison-laced injection by Thomas Kwan, 53, the son of his long-time lover Jenny Leung at the home they shared in Newcastle
Kwan is seen in a selfie wearing a disguise of a fake hairpiece, beard and moustache. He took this selfie in order to create a fake ID under the name Raj Patel
Kwan wanted his 73-year-old mothers inheritance but was concerned that her long-time partner, Patrick OHara, stood in the way.
And so it was he dreamt up an extraordinary plan that would use his medical skills and knowledge to attempt to kill his rival.
Having developed an encyclopaedic knowledge of toxins, earlier this year he tricked Mr OHara into thinking he was due a home health check-up from an NHS community nurse.
But on the day, Kwan himself turned up at the home Mr OHara shared with his mother, in disguise and adopting broken English and an Asian accent. It was good enough to fool his mother who even got him to check her blood pressure while he was there.
Kwan then injected Mr OHara with what he claimed was a Covid booster.
It was nothing of the sort. Almost instantly Mr OHara felt an agonising pain in his arm.
The GP, who wore a hat, tinted spectacles, gloves and a surgical mask, is seen checking into the hotel
Kwan, 53, a partner at a surgery in Sunderland, is seen in CCTV footage arriving at a Premier Inn in Newcastle wearing a heavy disguise
Two days later he was admitted to hospital with the flesh-eating bug that causes necrotising fasciitis and had to undergo emergency surgery to stop the infection spreading.
Police were called and were eventually able to trace the journey taken by the nurse all the way back to Kwans house, around 37 miles away near Stockton-on-Tees.
At the same time medics were desperately battling to work out what poison he had administered, even enlisting the help of a Ministry of Defence scientist with expertise in chemical warfare.
Following the discovery of Kwans garage laboratory, ricin was one of the chief suspects, although it is now thought the substance used was in fact a pesticide called iodomethane.
Thankfully Mr OHara survived. Kwan was charged with attempted murder (which he initially denied) and on Thursday last week his trial got underway at Newcastle Crown Court.
Emergency services outside Kwans £300,000 home in Ingleby Barwick, Teesside, earlier this year
Police officers were seen carrying boxes of evidence away from the large property
But after the prosecution had outlined their case to the jury, he yesterday pleaded guilty to attempted murder. Kwan was remanded in custody ahead of sentencing next week.
Judge Mrs Justice Lambert warned him: There will be a substantial custodial term.
Kwans plot to get his hands on his mothers money had been months in the making.
His mother, Wai King Leung, known to family and friends as Jenny, had been born in Hong Kong but settled in the UK with her son and daughter.
For more than 20 years she had been living with Mr OHara, a 72-year-old father of two and grandfather.
Ms Leung had worked on the tills at Marks & Spencer and, according to neighbours, had met Mr OHara, a loft installer, while he was working on her property.
He later walked across Newcastle and arrived at his mothers home at around 10am, introducing himself as the expected nurse
Kwan getting out of his car (middle) after arriving at the underground car park in Newcastle on the day of the attempted murder
The GP, who carried a large bag, is seen making his way up the stairs
A close up of the doctors face as he was walking up the stairs without a mask om
Her Georgian maisonette in a Grade II-listed building is located in Newcastle city centre, within earshot of St James Park football ground.
Patrick retired probably five or six years ago, a neighbour told the Mail. He worked away. We got on OK. Theyre ordinary people, nice to speak to. She seemed like a caring person. Shed say things like, You need to wear a thicker coat, put your hood up, get out of the rain. Its cold.
Another neighbour added: Patrick is a lovely lad, a Geordie. He was very quiet, but dead polite and a really nice personality.
Despite the length of his mothers relationship with Mr OHara, Kwan had only met him on a few occasions when visiting his mother. Even then there was only ever the briefest exchange of pleasantries.
More recently, relations between mother and son deteriorated badly – largely due to pressure from Kwan over her finances.
Ms Leung owned her £200,000 flat outright. Under the terms of her will, written in September 2021, Mr OHara would be allowed to live there for the rest of his life. Only when he died, or gave permission, could it be sold and the proceeds inherited by Kwan and his sister.
It is unclear if or why Kwan was under financial pressure.
In 2010 he paid £360,000 for his own, detached house on an executive development in the town of Ingleby Barwick. There is no mortgage on the property.
Police wearing Hazmat suits search the house belonging to the GP, as paramedics and firemen standby in specialist suits
Having completed his medical degree at Newcastle University in 1996, Kwan started work as a hospital doctor, before entering general practice.
Until his arrest he was working as a partner at the Happy House Surgery in Sunderland, a position that typically pays about £140,000 a year.
Nonetheless, Kwan continually badgered his mother about money – so much so that she stopped taking his calls or responding to his emails.
Then in November 2022, Kwan turned up at his mothers home unannounced.
He forced his way into the property, pushing past Mr OHara to get to his mother, pestering her once more about her financial affairs, prosecutor Peter Makepeace KC told the court.
The row was so bad Mr OHara called the police, who duly attended and spoke to Kwan about his behaviour. But aware how it might affect his job as a GP, the couple told officers they did not want the matter taken any further.
Kwan had other ideas.
At some stage he placed spyware onto a computer used by his mother and Mr OHara at their house. The court heard it allowed him to monitor emails and any internet searches undertaken.
In particular, he was monitoring his mothers financial dealings. (Using the camera integrated into the device he was also able to watch the couple as they used the computer, taking photos which he saved.)
Meanwhile, on his own computer Kwan started to amass a library of literature dedicated to poisons and poisoning. Books and papers downloaded included: Ten poisons used to kill people, The Mujahideen Poisons Handbook, The Terrorists Handbook and Forensic Science and Medicine: Criminal Poisoning.
Kwan also started to stockpile chemicals in his garage. Some were ordered through a company he set up and for whom he claimed to be working as a research officer. He gave its registered office as the surgery at which he worked, telling the practice manager there to forward anything delivered to the company to him. Substances obtained included thallium – a difficult to detect poison – potassium cyanide and iodomethane.
The next step in Kwans plan, the jury was told, was to find a way to administer the poison.
A large forensic tent was erected in the garden of the property
In November last year Mr OHara received a letter on NHS-headed paper, explaining he had been selected for a home visit by the community nursing team.
Its use of medical terminology, its deployment of NHS hyperlinks and data protection privacy notices gave it a chilling authenticity, the prosecutor told the court. In fact it had been drawn up by Kwan on his home computer.
A second letter followed in January, offering Mr OHara a visit on January 22.
The night before, Mr OHara even received a text message reminding him of the appointment. The message had been sent from Kwans phone, but using a sim card with a different number to his usual one.
Hours later, Kwan set off from his home in his Toyota Yaris, to which he had fitted false number plates.
Having checked into a Premier Inn in Newcastle, at 9am the next day he was caught on CCTV emerging wearing a long coat, flat cap and tinted spectacles. He had blue surgical gloves on and a clinical mask covering his face.
Arriving at his mothers house on foot, Kwan spent ten minutes going through a medical questionnaire with Mr OHara. He then took his blood pressure and drew two phials of blood for testing.
At one point Ms Leung came downstairs and, entirely unsuspecting, asked Kwan to take her blood pressure. He did this and then told Mr OHara he was eligible for a Covid booster, which was administered into his left arm.
Immediately Mr OHara felt a terrible pain and jumped back, the prosecutor said. He shouted Bloody hell and explained the immediate and intense pain, but the nurse reassured him it was not an uncommon bad reaction and it was nothing to be concerned about.
Kwan quickly packed his bag and left.
Emergency services descended on the £300,000 detached house at Brading Court in Ingleby Barwick, Teesside
Mr Makepeace continued: As he left the home, Ms Leung came downstairs and commented in passing that the nurse had been the same height as her son. Upon that comment, and for the first time, Mr OHara began to suspect something was very wrong.
A trip to A&E followed, where he was given antibiotics and painkillers. The following day the injection site was blistering and Mr OHara returned to hospital where he was diagnosed with necrotising fasciitis.
He then had a number of emergency operations would remain dangerously ill in intensive care for weeks as medics worked to try to identify the poisonous substance he had been injected with.
Police had been alerted following Mr OHaras admission to hospital. Using CCTV they were able to track Kwans journey to and from the house, all the way back to his home.
On February 5 the doctor was arrested for attempted murder, with searches conducted on his house and garage. Kwan refused to tell officers what he had administered.
But the discovery of the castor oil beans and associated ricin recipe led detectives to initially believe this was the toxin that had been used.
Only later did the focus shift to iodomethane, after a syringe filled with the pesticide was found in the garage.
The substance had never been used in a recorded poisoning before. Police believe this was no accident. It meant that unlike more established poisons like arsenic or mercury, it would be much harder to identity and to treat.
In other words if you want to not only inject a substance that causes necrotising fasciitis into a person but make it as difficult as possible for the medical team to identify the cause and treat the illness, iodomethane is the one to pick from the many substances available to Mr Kwan, said Mr Makepeace.
While the substance used may have been in doubt, Kwans role in the attack was not.
From his home computer, police recovered copies of the fake NHS letters sent to Mr OHara, as well as a copy of the tick-box questionnaire. A photograph was recovered from the same device showing Kwan in disguise with a wig, beard and moustache.
Ahead of the trial, while denying more serious charges, Kwan had admitted administering a noxious substance, claiming his intention was to cause mild pain and discomfort.
Not that Kwan showed any hint of remorse.
Even whilst in prison awaiting trial, his letters to his wife express zero regard for Mr OHaras life but a bitter complaint and resentment that he may be eligible for compensation, the prosecution barrister added. He is plainly disappointed Mr OHara may have survived to be eligible for such.
The Mail also understands that Ms Leung has now sold the property her son was so desperate to get his hands on.
Meaning that, facing a lengthy jail sentence and with no prospect of ever again working again as a doctor, Kwans evil plot could not have gone more wrong.