With the Scottish parliament back in action, there is one issue above all others dominating the conversations and thoughts of Labour people.
No, it's not the SNP's Programme for Government. Not Brexit. And not the forthcoming debate on raising taxes either.
Those important subjects all feature of course, but the topic which is uppermost in Labour minds is the race to replace Kezia Dugdale as Scottish leader.
I've been speaking to people over the last few days and have been surprised at their verdict on the battle between MSPs Anas Sarwar and Richard Leonard.
Here are just a few of the comments: "Close." "Very close." "Too close to call."
From these conversations with experienced hands we can safely assume it's going to be, well, close.
Why should I be surprised? Surely nothing in the modern Labour party can surprise any more?
After all, no-one thought Jeremy Corbyn could ever be UK leader, and he is - having won two party elections.
In Scotland the contest between Leonard and Sarwar might have been thought to be different from the parallel contest in the UK party.
Sarwar is a former MP, a former deputy Scottish leader, with a high profile and comes from what might best be described as the more traditional centre-left of the party.
His opponents put it more bluntly, and disparagingly. He's 'New Labour' they say. It's not meant as a compliment.
Leonard on the other hand spent his life in the trade union movement until he become an MSP at the last Holyrood election and is unapologetically from the Corbynite Left of the party.
Sarwar is slick, articulate, media-savvy, and has been judged to have recently made life uncomfortable for the SNP government over the issue of the NHS.
Leonard is relatively inexperienced in elected politics, and has not had a very high political profile.
Until very recently he did not even have a Twitter account.
Given all of that and the fact a survey by the YouGov polling firm suggested a majority of Labour members in Scotland backed Owen Smith over Corbyn in the UK party leadership election, Sarwar is surely a shoo-in?
Well, no. That is certainly not what Labour MSPs, staffers and party members I've spoken to think.
First, no-one really knows where Scottish Labour party members now stand on the Left-Right spectrum.
The electorate consists not just of fully paid up members but also 'registered supporters' who pay £12 for the privilege.
It is thought these registered supporters, who can still join, are likely to be inspired by Corbyn and therefore inclined towards Leonard.
As well as those people anyone affiliated to the party through a union by paying the political levy to support Labour gets a vote.
As Leonard has a background in the trades union movement he may well have the advantage with these voters.
Then there are the political differences.
Although Sarwar has recently presented himself as a Corbyn enthusiast, he was one of many MSPs who a little over a year ago called for the UK leader to step down.
When I interviewed him, for ITV Border's Representing Border, about this he told me simply: "I was wrong."
The question for him is will Labour members accept that?
Leonard on the other hand has been of the Left all of his life.
When I asked him if he had changed his view on anything over the last three or four decades, he replied "That's a very good question" and did not have a ready answer.
Those in the party who view the Left (the far Left as they would see them) as a malign force more interested in internal battles than winning parliamentary elections will see that as significant.
But there is one other aspect of this contest which no-one can predict the effect of.
Leonard and Sarwar are both the products of private schooling, though the former was a scholarship boy.
Sarwar and his wife have chosen to send their children to a private school in Glasgow, the same one he went to.
Now, he's not the first Labour politician to make that choice. Think Left-winger Dianne Abbot south of the Border.
There are others. But it is even less common in Scotland.
The question is will this have an impact on his support?
Most Labour party members have an instinctive dislike of private education and this very personal choice could potentially have a big political impact on Sarwar.
Even those who are not of the Corbynite Left but 'mainstream' Labour will, it is thought, struggle to vote for a leader who has chosen the private over the state sector for his children's education.
On the other hand, more pragmatic party members who have an even greater instinctive dislike of the Left argue that there is a bigger picture here.
While not enthusiastic about private schooling, they are effectively saying those like them should hold their nose on this issue and vote for Sarwar.
It is, they argue, the only way to save the party from what they see as the threat to their electoral prospects from the Left inside Labour.
Leonard and supporters on the other hand will not even have to mention the schooling issue as it has been well reported.
They firmly believe that Corbyn has shown the way that, as they would see it, a properly traditional Left-of-centre politicians can win over the electorate.
What Corbyn did in the UK election, Leonard can do in Scotland, they say.
As voting does not open until October 28, this intriguing contest has a long way to go yet but make no mistake, it is a battle for the political soul of Scottish Labour.