Like so much about North Korea at the time of one of the most historic world summits in history, life at the nation's embassy, nestled in the leafy West London suburbs of Ealing, is still shrouded in mystery.
As this week's potentially world-changing summit in Singapore takes place between Donald Trump and Kim Jong-un, our reporter Martin Elvery paid a visit to the embassy.
Perhaps you wouldn't expect North Korea - a famously secretive nation widely seen as having the most brutal dictatorship in the modern world - to have an embassy at all in the UK, let alone in Ealing.
But perhaps the strangest thing about the embassy is just how easy it is to find.
Given North Korea's well publicised secrecy, you might expect that its embassy would be hidden away in some kind of bunker, but a quick search of Google gives you the location and there's a big bronze sign next to the front door which reads Embassy & Office of DPR Korea. It's all rather obvious.
I walk towards the embassy, along Gunnersbury Avenue, a street of beautifully presented 1930s Metroland villas, just around the corner from the stately Gunnersbury Park.
It's a lovely location with a "Queen of the suburbs" air. If North Korea is really so short of cash, it could certainly do worse than flogging off this nice little nest egg.
When I arrive, the low wrought iron gates of number 73 are, of course, closed and the shut windows of the elegant bay-fronted house look as if they have blinds drawn or curtains closed behind them.
The front of the house is surprisingly open to the street. There are no high fences or spikes. But then I notice a CCTV camera on the front wall peeking at me.
After several phone calls to try to set up a meeting with the ambassador simply ring off, I decide to try the door bell - but there is no sign of movement. Not even a curtain twitching. I try again. Still nothing.
A glimpse around the side of the house reveals a long, high wall, obscuring any views into the rear of the property and large wooden double gates, painted black. This is more like it.
A peek through the hinges and there's a black diplomat's car parked on the grass looking as if it could be swung out through the gates at a moment's notice. The rear of the house again looks completely sealed up.
I decide to try the neighbours to see if there's any sign of the staff. They are mostly out, but one lady who lives next door tells me she she knows little about the embassy's residents as she has only just moved in.
She says she thinks there is a husband and wife, some children and maybe some servants, but can't say any more than that.
No-one seems to be answering at any of the other houses which are equally large suburban villas that seem eerily quiet.
Of course conspiracy theories are starting to take over my thoughts but I try to keep them in check. "It's perfectly normal, they are just out for the day," I think, and yet ...
In my mind I'm in a 1950s Cold War thriller. But am I doing the spying, or being spied on? I can't tell.
I notice a large post box on the street outside. It looks freshly painted in bright Royal Mail red. Is it too conveniently close? Why the new lick of paint?
A postman parks his van on the street corner and gets out with some large parcels. He seems to walk very slowly past the embassy and glance towards the front door. Is it my imagination, or does he linger a little too long before walking further along the street.
Next minute I turn round and he's stood right next to me. "Hi...I'm a journalist," I mutter. "Do you know anything about the North Korean embassy, do you ever deliver there?"
He chuckles and gives me a knowing smile.
"I've only just started this round, I don't know anything about it," he says.
With a chuckle, he adds: "You'd better make an appointment."
I walk away, it's obvious nothing is going to give. Only in my imagination is the front door going to be opened by a silent man in military uniform who is going to beckon me into a panelled office for a "discussion" with the ambassador who will greet me with the phrase: "We've been expecting you Mr Elvery."
I wander back to my car. I feel I have failed. Somehow I should have been able to shed some light on this mystery. Or somehow I should have done my little bit to help improve relations at this crucial moment in world history. I've missed the boat.
But then I drive past again on my way home, expecting nothing to have changed. This time, though, there's a black diplomat's car parked on the front driveway.
I try the phone again. It rings a few times, then crackles into life. An abrupt staccato voice answers, "Hello".
"Hello there," I stammer. "I'm a local journalist. I'm just trying to see if I can set up an interview with the ambassador.
"Hold on a minute," the man replies. "I'm on the other line."
Then after a delay: "Hello. Please email your enquiry to firstname.lastname@example.org."
I try to ask more questions but it's clear the conversation is over.
I stop the car and quickly scribble a polite email requesting a contact or an interview. Then I drive slowly away, my head buzzing with unanswered questions.
To be continued ...
What we do know about the embassy?
- North Korea purchased the house for £1.3 million in 2003.
- As reported in The Telegraph in November 2014, in an effort to improve relations, a public exhibition of North Korean art was held at the embassy, to coincide with the visit of four North Korean artists to London. Reports carried by the newspaper from people who were invited to the event suggested they were being watched very carefully.
- The former deputy ambassador Thae Yong Ho defected to South Korea in 2016. The ambassador at the time was Hyon Hak-bong. Mr Hyon was reported to have been recalled to North Korea following Mr Thae's defection.
- According to The Telegraph, Mr Thae's main duty had been to improve North Korea’s public image and he gave a number of talks to local communist societies in West London extolling the values of North Korea’s authoritarian "Juche" ideology, which is often translated as self-reliance.
- On the night of Mr Thae's defection, neighbours apparantly reported a flurry of activity outside the embassy and he was spirited away with his family to Soeul in South Korea.
- Following his defection, Thae Yong Ho revealed how he had been asked to report back to Kim Jong-un's secret police about any signs of disloyalty or communication with Brits among the embassy staff.
- On September 25, 2017 the embassy was evacuated after a suspicious package was found. Police attended and a controlled explosion had to be carried out.
- Ealing barber Karim Nabbach of M&M Hair Academy claimed he was visited and threatened by two North Korean officials in 2014 after he put a picture of Kim Jong-un in his window, offering a discount to customers having a "bad hair day". The officials, he alleged, demanded the picture be taken down but the salon owner called the police. The story made international news headlines.
- In 2017 The Sun newspaper rented a propery next door to the embassy through Airbnb. Its reporter Richard Wheatstone told how embassy staff were sometimes heard having barbecues in the back garden.