In the 1990s, Lloyd's found itself facing huge payments on claims over asbestos and pollution. The financial burden fell on the Names, who were called on to fund the settlements. His share was $344,000.
The demands to meet Lloyd's obligations placed enormous pressure on the Names. Some killed themselves. About 1500 were made bankrupt. "It has ruined my financial life," Dr Simpson told the High Court.
He said Lloyd's had been "fraudulent" and "negligent" when dealing with "us downtrodden Names". He and three others fought the market through court - a battle they lost. The decision, he told the court, "wasn't a judicial decision, it was political".
Lloyd's pursued Dr Simpson for the money and the closer it got, the further away he moved.
He left his practice as a psychiatrist in prestigious Harley St, moving to Hong Kong, where he became firm friends with millionaire New Zealander Carrick Clough, whom he had first met skiing in France in 1982.
When the $344,000 judgment was entered against his name in 1998, Mr Clough and Dr Simpson were already enmeshed. They went into business together, while Mr Clough bought the riverside Hamilton home in which Dr Simpson would later hide his treasure.
Life settled into a pattern - Dr Simpson challenged the debt, unsuccessfully, while Lloyd's Names succumbed to bankruptcy or death.
He moved to Hamilton, attended St Peter's Cathedral and attempted to move his money out of the system.
He turned much of it into gold, silver and precious coins. He later told the court he had made up to 20 visits to Auckland to buy gold, silver and rare coins. "It's a chore - you have to go for the day."
Other money was hidden under the alias James Walter Smith or in accounts he was not directly linked to.
Each winter, he left for England and his beloved cricket season at the famous Marylebone Cricket Club. That is where friends believe him to be now.
Dr Simpson was made bankrupt in August 2009. The official form, filled out by Dr Simpson, listed an income of $347 a week. He wrote: "Lloyd's were a waste of time," calling the money owed an "alleged debt".
Asked for the reason behind his bankruptcy, he wrote: "Lloyd's of London disastrous underwriting."
Insolvency officer Steven Williams wrote to Dr Simpson, asking for written permission to search the world for assets. Permission never came. English authorities hired Waikato lawyer Kalev Crossland, who went to the High Court to ask New Zealand to adopt the case as its own.
He knew it would be a world-leading case but it became much more. "A case like this only comes along once in a blue moon."
The court appointed Official Assignee Les Currie to investigate. "I like to deal with facts," he says. "I like to do my own research, I never jump the gun. As long as you keep your eyes and ears open, you never know what you'll find."
The first search of Dr Simpson's home turned up safes - in the study, in his teenage daughter's bedroom, in the garage and in the "heater" room.
The search was a surprise to Dr Simpson. Court records state that about 40 minutes after it began, eagle-eyed Mr Currie saw the bankrupt trying to hide a scrap of paper.
One court document speaks of Dr Simpson being stopped while lunging towards the toilet, intent on flushing away an eftpos receipt. It was handed to Mr Currie, who studied it and handed it back - he had already tracked the account.
There was still bullion missing. Mr Currie was called and told of hidden compartments. Back they went, finding one hidden in the dining room and another set back under the house.
The builder had been told Dr Simpson believed the end of the world was coming and he needed somewhere to stash survival equipment.
By the time Mr Currie was finished, Dr Simpson's world hadn't ended - but it had changed forever. The $344,000 debt had ballooned to $1,291,000. The bankruptcy had attracted other debts, including a $500,000 bill from Mr Currie for the work it took to drag Dr Simpson's wealth into the light. After paying his dues, he was left with $1 million.
The New Zealand case has since been used in British courts. It was leaned on in Australia just last month, in the case of a bankrupt from South Africa. The consequences are far-reaching. Quite simply, says Kalev Crossland, "it shows you can't hide."
