Jamie T on his a six-year silence, oligarchs, and Kim Jong-Un

It's not every day you hear a love song about Kim Jong-Un.

But if you fire up Jamie T's new album and skip to a track called 50,000 Unmarked Bullets, that's exactly what you'll find.

The lyrics are slightly cryptic, but a reference to a "boarding school in Gumligen" unlocks the puzzle- because that's where Kim allegedly studied as a teenager in the 1990s under the name "Chol-pak".

"Well done! Good research," laughs the singer, full name Jamie Treays, when I put the theory forward.

"Um, how do you explain that you wrote a song about Kim Jong Un?"

The explanation is actually pretty solid. The song started as a writing exercise, in which he tried imagine a situation "where you feel sorry for the son of a dictator".

"The whole idea is that he's at The Hague on trial for war crimes but he's worried that the transcripts don't show quite how romantic his time at baccalaureate school with his girlfriend was," says the singer.

"He doesn't want her to hear the transcripts, because that's their romance ruined - and he's more bothered by that than anything."

Combining poignancy with clever wordplay and a chorus that David Bowie would have coveted, 50,000 Unmarked Bullets is a timely reminder of Jamie T's genius.

Described as an "indie national treasure" by the NME, and "a rare, cocksure talent" by BBC Music, the Wimbledon-born singer burst onto the scene 15 years ago with the scrappy and rebellious Panic Prevention.

Crammed with stories about teenage misadventure, it also signalled his potential on Sheila, a moving portrait of an abused woman, earning a Mercury Prize in the process.

Treays quickly followed it up with Kings And Queens, a more polished, but no-less weighty, album that channelled both the jagged energy of The Clash and the everyman poetry of The Streets.

Then, suddenly, he disappeared for five years, maintaining a silence so complete that fans began to question whether he was still alive.

Luckily, he was. But exhaustion from touring led to a sort of creative crisis, during which he became embroiled in a pub fight that led to charges of GBH (he was later cleared).

He returned to music in 2014 with the arms-aloft indie anthem Zombie; before 2016's genre-blending Trick garnered the best reviews of his career.

But there's been another six-year gap since then. So what happened?

"The answer is really boring," he shrugs. "It just took me that long to write something I thought was good enough."

A notorious over-writer, Treays composed more than 200 songs for his new album, The Theory Of Whatever. His output was so prodigious, in fact, that the aging Apple Mac in his studio finally gave up.

"It's like, 'I'm off. I'm leaving the band'," he laughs. "Not turning up for rehearsals, always in a filthy mood."

Condensing that material into a coherent album was easier than it sounds, however. Treays constructed endless playlists as he worked and, over time, the best ones tended to stick around.

And yet, the song that held the key to the album almost slipped through the cracks.

Called The Old Style Raiders, it bridges the gap between Treays' raucous early material and his new, more reflective outlook.

With a big, stroppy guitar riff and a lyric about fighting for the things you believe in, it languished, forgotten, on Treays' hard drive for six months before he stumbled across the file one night.

"I was really upset, because I realised that I'd spent the last six months asking other people to tell me if something was good. Then I heard this track and I just immediately knew I'd kind of found my path," he explained when the song was released as a single in May this year.

Elsewhere, his fifth album tells familiar stories of drunken nights out, "dirty promises" and sleeping around - while exploring how those misdeeds destroy relationships.

The theme recurs so often that it's easy to assume the songs are ripped from the pages of his own life. But Treays has never talked to a journalist about his personal affairs, and that's not about to change.

"I think it's a mistake in art, in music, that people think we're writing a manifesto or a diary," he says.

"My ability to write songs, and to be honest, and to be brave, comes with a caveat of not having to tell you what I'm doing."

When he sings about "doing too much coke" and being "caked in mud, piss and blood", it could be based on experience, observation, imagination or a mixture of the three.

"It's a conundrum you'll have to live with," he smiles, before offering this observation: "You don't have come across well in songs, you know? It's not like a rom-com. It doesn't have to have a happy ending."

He's more comfortable talking about St George Wharf Tower, a mournful acoustic ballad, named after London's tallest residential skyscraper. More than two-thirds of the apartments there are in foreign ownership, with the residents list including Russian oligarchs and Kurdish oil tycoons.

The song was partly inspired by a walk through the deserted streets of Chelsea one Christmas Eve, with a former girlfriend who worked in design.

"She'd worked with a lot of these oligarchs and she was telling me how gaudy these houses are inside. And as we walked, she was saying, 'I worked on that house, that house, and that house - and none of them is actually lived in.'

"So [the song] came from that feeling of what a shame that is, that no one lives in these houses, which contributes to the housing crisis and all that.

"It's kind of sad, isn't it, to have your city taken over by people who don't live there?"

London has been a character in his songs since the beginning - whether he's stuck in Hampton Wick after missing the last train home (Sticks 'n' Stones), avoiding crackheads at Nelson's column (Peacemaker) or mourning the closure of his favourite venues (Sign Of The Times).

He still lives in the city, surfacing every couple of years with new music, and finds the prospect of being back in the spotlight "a bit unnerving".

"After shows, people grab you and want to take photos with you, and my anxiety goes through the roof," he told The Guardian in 2016. "To this day, I find crowds of people quite difficult."

He's consistently addressed mental health in his music, even before it became a publicly-accepted topic of conversation. His debut album had an underlying narrative about panic disorder - even using samples of a self-help tape for anxiety sufferers.

He wasn't deliberately breaking taboos or trying to be brave, he says. "It just felt like me. But I think a lot of people gravitated towards the album because of that."

In fact, the album has become a minor modern classic - recently going platinum for the first time.

"I would never have thought I could sell that many records," he marvels, although he lost the award almost as soon as it arrived.

"Someone told me I left it at their house," he laughs. "I don't like having those things around for myself. You won't find them on my toilet wall.

"But mum and dad are really happy about it, so I get those things for them, really."

That modesty and lack of concern about external validation are the very things that have kept Jamie T at the top of his game for the last 15 years.