I met the notorious billionaire building £100m palace that's been unfinished for 30 years

Billionaires who've been charged with murder don't normally give interviews.

So when I got a call from Nicholas van Hoogstraten's son telling me the family was open to talking to me for an article I was writing on their unfinished £100 million palace in Sussex, I was more than a little surprised.

Type Mr van Hoogstraten's name almost anywhere online and you'll quickly see some arresting content. He's been called "Beelzebub" by judges and describes himself as "violent."

A vast list of articles and videos will tell you how he was convicted of paying a gang to throw a grenade in a debtor's house and stood trial at the Old Bailey for the murder of a former business associate (a crime he was subsequently cleared of).

Dig deeper and you might also come across the remarkable old documentary where Hoogstraten arranges for the journalists to speak to a man he allegedly kidnapped. The footage shows him sitting in on the interview where the victim describes in trembling tones how he was bundled into the boot of a Rolls-Royce, driven to France and beaten to a pulp.

Examine coverage from the 80s and 90s, there are stories of his ruthless money lending and brutal approach to being a landlord. Oh, and due to his vast land ownership in Zimbabwe, a well-documented friendship with one of Africa's most notorious dictators, Robert Mugabe.

I absorbed the entirety of this mad story of violence, power and wealth before meeting the man himself. And, as you'll appreciate, I therefore expected a tricky encounter.

His wild past was only the background, however, as the crux of the conversation we were due to have was about his one enduring mystery: his uncompleted Palace.

My task was to try and get some answers to why work was abruptly halted in the late 90s just as it was nearing completion.

I was also tasked with understanding what exactly he wants to do with the site, which has remained frozen in time for three decades.

But when I meet the man himself, the mystery of the unfinished mansion melts somewhat into the background.

He wants to discuss so much more: the 'bullshit' murder charges, the 'bullshit' grenade attack and the abominable state of the world 'headed for Armageddon.'

For most of the conversation, I just have to sit back or gently steer us back to the topic of the mansion.

And, as he rages about the stupidity of a design error on the mansion or sneers at the idea he might earn £10K from social media, I'm struck by just how performative his hard edge is.

Obviously, he has been convicted of serious offences and shouldn't be taken lightly.

But I can't help but notice how deliberate the narrowed eyes and swearing are.

The impact of those moments is lessened considerably by the equal amounts of nostalgic smiles and discussions of family.

Perhaps age means I'm encountering a softer version of the man, but his occasional hard stares and comments about "chopping people's bollocks off" don't land quite so hard when he's also getting lost in a lecture about Tiny Rowland or John Paul Getty.

Clearly, he is a man who gets angry. I can see that with the way he seethes about past grievances, even ones that are decades old.

But I wonder whether he cultivated the tough guy persona as both a defence mechanism and a business necessity.

His son, Max Hamilton, tells me that he is wary of the media because of the way he saw it affect his father and describes his dad's life as being split into two parts: before and after the murder case.

That sounds plausible, although it's impossible to tell from just a couple of hours' meeting.

The public record shows some pretty brutal assessments of Hoogstraten's character, but still, I find it difficult to determine how much bite really exists behind the bravado.

My mind is drawn to the legendary pirate Captain Blackbeard, who built a reputation so fearsome that violence was often unnecessary.

The crews on the ships he raided were already so terrified that they just submitted.

This is not to say Blackbeard wasn't a ruthless and brutal leader - but he was shrewd enough to know that being a legendary bad guy is often just as effective.

You can find out exactly why Hoogstraten abandoned his Palace before completion here.