EVERYONE loves a good mystery. The Scottish Conservatives certainly do. The installation of Douglas Ross as their third leader in a year is proof of that. He is impressively anonymous.

But after Jackson Carlaw proved such a dull and dated read, the party hope they’ve found a gripping page-turner in the younger MP for Moray.

There’s also his intriguing “joint ticket” with Ruth Davidson, who will lead at Holyrood until he arrives next May via the Highlands list and she decamps to the House of Lords.

Mr Ross may lack a national profile, but he has a solid CV, including time at both Holyrood and Westminster, and a spell as a Scotland Office minister.

He quit the latter role in May to register his disapproval at the Dominic Cummings scandal, the only UK minister to resign over the issue.

He also has an interesting sideline as a top class football referee.

But despite becoming Scottish leader unopposed on Wednesday, it had not been a top class week.

He tripped on his laces on day one.

After he and Ms Davidson used a newspaper article to bemoan Tory “defeatism”, Mr Ross carelessly conceded defeat by saying he hoped to provide “opposition to the SNP”.

But the bigger stumble was in the way Mr Ross became leader.

All parties have their plots, and the ability to execute them - or spot them coming - is a necessary skill in a leader.

Voters know this, and I reckon they aren’t too squeamish about it.

But what sticks in the craw is when politicians feign wounded innocence, or worse still mislead people.

Mr Ross’s coronation has come with a steady drip of clues about his part in Mr Carlaw’s assisted resignation.

Besides Boris Johnson and Michael Gove recently meeting him, it emerged Ms Davidson also made the 340-mile round trip from her home to Mr Ross’s just four days before the Scottish Tory leader was surgically removed.

Despite the circumstantial evidence of a stitch-up, Ms Davidson scoffed at the idea on BBC Scotland’s The Nine.

“He asked me if I would get on board and help him.” Before Jackson Carlaw resigned? “No, no, no, after.”

Pushed on whether it had been a carve up, she said: “I’m terribly sorry, I don’t know what else to say apart from ‘Jackson Carlaw resigned, Douglas has put his hat into the ring, I think he’s the best person for the job, I’m backing him and doing all I can to help.”

But even a masterful non-denial denial is never as good as the truth.

Mr Ross has the same improbable chronology on his campaign website.

“My first act on Thursday evening after Jackson Carlaw honourably announced his resignation was to speak to Ruth Davidson and ask her to support me in my plans.”

His first act? For such a life-changing decision, you would think he’d talk to his family first, especially as the father of a one-year-old.

Although there’s also that Freudian slip at the end about “my plans”, which suggests his leadership bid wasn’t exactly spontaneous.

Mr Ross didn’t clarify things yesterday, when he was asked what he and Ms Davidson had discussed.

It was, he said, a “private meeting”.

The iron secrecy seems a bit odd for a social visit, so presumably weightier matters were indeed on the agenda.

“What I have said is that I asked Ruth, and she agreed, to lead FMQs if I become leader only after Jackson resigned,” he said, which again leaves a lot unanswered.

Ms Davidson also has form on stitch-ups. When she ran for Scottish Tory leader in 2011 it was a bitter affair, with her three rivals, including Mr Carlaw, complaining she was being unfairly helped by party HQ.

The party’s spindoctor at the time, Ramsay Jones, who was supposed to be neutral in the race, was found to have been at her house on the night of a campaign meeting. She denied he’d been part of it, but later admitted the pair “probably did get on to the campaign” at some point. Mr Jones was suspended, and left to work in Downing Street. He’s now a CBE.

Ms Davidson’s campaign manager was the MP John Lamont, who was also Mr Ross’s campaign manager.

He’s a fast worker. Five Douglas Ross for Leader websites were registered within an hour of Mr Carlaw announcing his departure. Suspicious or just devilishly efficient?

In fact, there is a smoking gun. Well, some smoking metadata. Mr Ross’s campaign website carries a ‘Douglas Ross for Leader’ logo, and embedded in that logo, for those who know how to find it, is an electronic timestamp which shows it was created just before Mr Carlaw’s resignation statement. Now that is uncommonly fast work.

Well, so what, you may think. Politicians will be politicians.

But other Holyrood stories this week showed why the Ross-Davidson flannel could have wider significance.

The inquiry into the Alex Salmond affair will be one of the biggest things on Ms Davidson’s plate when she returns to FMQs. It will be her job to prosecute the case for the Tories and wound Ms Sturgeon and the SNP ahead of the election.

This week, we learned the FM withheld details of a relevant meeting about Mr Salmond from MSPs last year, and the Scottish Government also withheld reams of evidence from the inquiry on legal grounds.

The Scottish Tories are now demanding full transparency.

It will not be easy for Ms Davidson.

Always remember that Ms Sturgeon was a lawyer before Holyrood.

Her words are precisely chosen.

I doubt very much that she directly misled MSPs with a bald lie.

However it does look as if MSPs have been misled by omission, with the First Minister telling them bits of the truth, but not the whole truth, and then letting a false impression take hold and doing nothing to correct it.

But anyone planning to attack her on transparency grounds, with these high stakes, needs to be spotless, the very model of transparency.

Questions over Ms Davidson and Mr Ross’s candour, and the series of extreme coincidences leading up to Mr Carlaw’s departure, offer Ms Sturgeon a glimpse of a way out.

‘Why should I take lectures from this humbug with her record? Who is she to judge me?’ she may say.

Besides insulting our intelligence, Ms Davidson has already hamstrung herself in the contest to come.