For the next couple of weeks, the sun may not shine but the Scottish capital Edinburgh will enjoy the spotlight anyway.

The streets are packed with tens of thousands of visitors there to enjoy a smorgasbord of entertainment: music, comedy, drama, literally hundreds of shows squeezed into every possible venue for the Edinburgh Fringe Festival.

But beyond the curtain calls, the encores, is another drama building to a tense final act.

It's called Brexit, and its consequences for the existence of the United Kingdom, and Scotland in particular, are far reaching.

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Hundreds of kilometres south in that land called London, the new British Prime Minister, Boris Johnson, has promised everyone the nation will be out of the European Union by the October 31 deadline, deal or no deal.

That's despite dire warnings from the Bank of England, the Chamber of Commerce and the former chancellor of the Exchequer that a no-deal Brexit will seriously disable the economy. Everything from a slowdown to a full-blown recession is predicted.

But Mr Johnson is ploughing on, fulfilling his promise to honour the 2016 Brexit referendum in which Britons narrowly voted to leave 52 to 48 per cent.

With a hostile Parliament and enemies within his own Conservative Party, it looks like an election is inevitable and could be called as early as in the next few weeks.

But — warns Mr Johnson — it will not happen before his Brexit job is done.

'Scotland has become a modern, European nation'

Some in Scotland say they are more European than British. ( Reuters: Russell Cheyne )

So, what's all that got to do with Scotland? North of Hadrian's Wall, the Scots voted strongly to remain in the EU. So too did Northern Ireland.

Neither is happy Mr Johnson is forcing them out of an entity the majority there see as a plus.

The whole Brexit crisis had triggered a dangerous debate in Northern Ireland about how to treat the border with the Irish Republic, which some fear could reignite The Troubles.

In Scotland, the Scottish National Party (SNP) governs in coalition with the Greens. For the SNP the Brexit debate is a gift, supercharging demands for a second independence referendum that could see the break-up of the United Kingdom as we know it.

Anand Menon, a European politics and foreign affairs professor at London's Kings College, says it's as dramatic as it sounds.

"When it comes to Scotland, it's fascinating because on the one hand, Brexit has confirmed everything that people who believe in Scottish independence always thought: 'The English are bastards that are ripping us out of Europe. They're wrecking our economy. Look what they're doing to us. Can you not see we should be governing ourselves?'," he told Four Corners.

I ask a stark question of the SNP's Mike Russell, Scotland's constitutional secretary, who is responsible for Brexit negotiations with Westminster: Will the advent of Boris and Brexit speed up Scottish independence?

"I think at the present moment, then the likelihood is that Boris Johnson's Prime Ministership will be the last prime ministership of the UK as it presently exists," he said.

"I think that the new Secretary of State of Scotland is likely to be the last secretary of state for Scotland. I think the reasons for that are many and varied, some of which have been around for a long time.

"Scotland has become a small, modern European nation, an outward-looking European nation.

"That has been a process that's been underway for several generations. The rest, well particularly England, hasn't gone in that direction."

'An insult to Scotland'

Mr Johnson will not want to go down in history as the man who won Brexit and lost Scotland.

His retort to the Scottish doubters is a call to optimism — the British can-do spirit that will usher in a glorious new prosperity.

Mr Russell echoes the opinion of the Welsh First Minister, who described Mr Johnson's approach as "vacuous optimism".

"It is silly, and it's damaging and dangerous," he said.

"This is the economics of the madhouse. It is also the politics of the madhouse. And Scotland of course voted against it. Scotland voted not to leave the EU. And were there another referendum on that tomorrow, it would vote I think in even larger numbers. So it's not only wrong to happen for the UK, it is an insult to Scotland."

Boris Johnson and Brexit have reignited the push for Scottish independence from the UK. ( Reuters: Paul Hackett, file photo )

In the 2014 independence referendum Scots voted 55 to 45 to stay with the United Kingdom. But in a recent poll, that's now at 52 to 48 for separation.

If that does reflect reality, then what's changed is Brexit, and Boris.

Of course, leaving the UK is not strictly up to the Scottish Government. If it had been, it would have done it already. Westminster has to give permission for another referendum, one which Mr Johnson is unlikely to agree to.

But at the next election the SNP could name its price for joining a coalition government with the Labour Party and the Liberal Democrats.

And, if the SNP picked up seats in such an election, then that in itself ups the ante for another vote on independence.

Mr Russell says opinion has shifted in Scotland.

"When I meet people, many of them will say to me, 'we weren't sure in 2014' — some voted yes, some voted no — 'but now we believe that that's what we should do'," he said.

"Now the argument has to be made. The debate has to happen. The people of Scotland have to make a choice.

"But when they look at what is happening south of the border, it does sharpen their thinking about this issue."

When Mr Johnson visited Edinburgh recently, he was not greeted by a 21-gun salute or a pipe band.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 27 seconds 1 m 27 s An Edinburgh crowd boos the UK Prime Minister

As Scotland's First Minister Nicola Sturgeon gave a frosty welcome to the new Prime Minister, there was a chorus of boos from the crowd. Of course, he does have his supporters in Scotland, but they weren't out and about that day.

The assembled gave the impression Mr Johnson was as welcome as a maggoty haggis.

'That union has had its day'

With a lone piper playing Scotland the Brave in the background the "bollocks to Brexit" campaigners are busy along Edinburgh's golden mile.

Half a dozen people are encouraging passers-by to sign a petition calling for Brexit to be stopped. They're doing good business, putting stickers of a combined Scottish and EU flag on people's chests.

It's fertile ground for those who are uneasy about the Brexit idea and its English chief salesman.

Mr Russell says former UK PM Theresa May used to talk endlessly about a "good Brexit", but he says there's no such thing.

"Brexit is a foolish thing. It should never have happened," he said.

He says Scotland can salvage something from Brexit — and it may mean leaving what Mrs May used to call this "precious union" — the union between Scotland and England.

"That union has had its day," Mr Russell said.

There is endless debate about the economic consequences of a hard Brexit. A crash out of Europe is looking increasingly likely followed very quickly by a general election.

As a little boy, Mr Johnson wanted to be world king, so perhaps more than most prime ministers, he will want a dramatic legacy; a memorable period in power marked by achievement and action.

But he will not be recalled fondly by many if the cost of Brexit is a return to violence in Northern Ireland and a dissolved kingdom with a new border between England and an independent Scotland.

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