Nicola Sturgeon's bombshell decision to step down as First Minister marked a tectonic shift in Scottish politics.
As the longest serving Scottish premier, Ms Sturgeon maintained a steely grip on power over nearly nine years in office, leading the party to dominance following a landslide victory in 2015 general election which left Labour with just one MP north of the border.
But a string of political rows appeared to take its toll, culminating in Ms Sturgeon's shock resignation in February.
At the time, she insisted it was not due to "short term pressures" and instead blamed the "brutality" of life in frontline politics.
But since she announced her resignation, events have escalated which could leave her political legacy in tatters.
Today, her husband Peter Murrell was arrested as part of a police probe into the SNP's finances.
Mr Murrell, the party's ex-chief executive, was hauled in for questioning as police searched the couple's Glasgow home and SNP headquarters in Edinburgh.
Police Scotland have been investigating the spending of around £600,000, which was earmarked for Scottish independence campaigning.
Mr Murrell quit his post last month after a separate row over the SNP's membership figures.
It marks the latest twist in a dramatic turnaround in the fortunes of the SNP, which has been in power in Scotland for more than 15 years.
New First Minister Humza Yousaf, who only took over from Ms Sturgeon last week, described the arrest as a "difficult day" with the party.
He told broadcasters: "My reaction, as you'd imagine, much like anybody involved in the SNP, is that this is a difficulty for the party.
"But, again, I'd just reiterate and emphasise it's so important for me not to comment on a live police investigation and be seen to prejudice that in any way, shape or form."
Asked if the arrest would hurt the SNP in the polls, he said: “It certainly doesn’t do us any good.
“People will have questions, there will be some concerns. Our party membership will have concerns too.
“What I can commit to as party leader is that we want to be absolutely transparent.”
He insisted the police inquiry wasn't the reason for Ms Sturgeon's departure - and said her legacy "stands on its own".
She told Sky News last month it played no part in her decision to step down.
Asked if she'd had any contact with police, she said: "No. I wouldn't comment on any ongoing police investigation and I am not going to comment on this one."
The latest drama comes after a bitter leadership contest which shone a light on the deep divisions within the party over its strategy on independence and transgender rights.
Rishi Sunak has made it clear the UK Government won't allow another independence referendum, and Ms Sturgeon's divisive plan to treat the next election as a de-facto second vote on leaving the UK is now in doubt.
Westminster has also blocked a Scottish Government bill making it easier for people to legally change their gender. Failing to challenge this could threaten the SNP's powersharing agreement with the Scottish Greens at Holyrood.
The SNP also face big challenges on the day-to-day running of Government - clearing the NHS backlog, stamping out poverty and Scotland's drug deaths epidemic.
Labour has been emboldened by the chaos as the party rides high in the UK polls.
The first poll since Mr Yousaf took charge showed the SNP lead over Labour in a general election cut to six points.
The Savanta survey put the SNP on 39%, with Labour on 33%, with SNP support falling by 4 points, and Labour's rising by 2.
Winning more seats in Scotland will be critical for Keir Starmer in the battle for the keys to No10 - and for campaigners against Scottish independence.
As for Ms Sturgeon, she has said she will remain as an MSP until at least the next election and take some time out to consider her future.
What her political legacy will be when the dust has settled remains to be seen.
