Heard the one about Salmond & Sturgeon being a new Burton and Taylor?

Also this week, BBC Scotland announced a new documentary, Salmond and Sturgeon: A Troubled Union, to mark the 10th anniversary of the independence referendum.

Featuring new interviews with both former First Ministers and other key figures, including current FM John Swinney, the makers Firecrest Films promise “an emotional tale of ambition, power and broken friendships [that] reveals the human cost of devoting your entire life to a political cause”.

Phew. If that seems overblown at first, a glimpse at recent history might make you think again. Where does one start? The blizzard of headlines, a landmark trial, claims of a vast conspiracy at work, official inquiries, all at huge cost to the public purse. Lest we forget, the story is not over yet.

Looked at in that light, Salmond and Sturgeon are the Burton and Taylor of Scottish politics - minus the marriages and diamonds, of course.

Their strictly political partnership is hardly the first to prompt comment. There is something about politics at the top levels that lends itself to drama: the high stakes; the pressured, Cat on a Hot Tin Roof environment; the driven characters obsessed with winning.

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Add rivalry between individuals - one of the oldest plots known to humankind - and you have the stuff of endless documentaries, dramas, books, and articles, of which this is one.

Other pairings linked by fate include Blair and Brown, Johnson and Cummings. Further back, Thatcher and Lawson, Thatcher and Howe, Thatcher and any number of others. Harold and Marcia. Even Churchill and Attlee had their tussles. When such partnerships work, good things can happen. But if they turn bad, governments can be shaken to their foundations and leaders ousted from power before they are ready.

You can see the beginnings of the process in the new Labour government. Even before Keir Starmer became Prime Minister, the media portrayed his relationship with the party’s deputy leader as a rivalry. Were the two at odds over policy, Rayner the Radical versus Steady as he Goes Starmer? It’s a safe bet any future differences between the pair will be picked out and magnified. Before you know it, Rayner and Starmer will be the new Blair and Brown.

Though the individuals concerned vary widely, political partnerships share certain characteristics. First, there is an initial imbalance of power, a mentor and a mentee. When Blair and Brown became MPs in 1983 it was the latter who was by far the more experienced and polished. Blair was smart enough to watch and learn.

Alex Salmond was quick to spot Nicola Sturgeon’s potential. With him cheering her on, she stood in Glasgow Shettleston at the 1992 general election. Though she lost to Labour the then 21-year-old was on her way. “He believed in me long before I believed in myself,” she has said of Mr Salmond’s backing.

Elected to the Scottish Parliament in 1999, Ms Sturgeon rose through the ranks. After just five years she felt ready to run for the leadership, but it was too much too soon. Mr Salmond returned, with her as depute, and the two eventually achieved what many Scots thought they would never see - a referendum on independence.

We know how that chapter ended. The story continued but everything was different. She became leader, he went back to Westminster. She was now First Minister with all the opportunities for self-promotion that went with the position, he was an MP, one of many. She was an election winner, he lost his seat in 2017.

Was it the beginning of the end when he fronted his own show on RT, or were the cracks evident before then?

Recollections may famously vary, but by the time #MeToo came along and Ms Sturgeon ordered an overhaul of HR procedures for dealing with claims of bullying and harassment, the Salmond-Sturgeon friendship was fading. The age of Cleopatra was in full swing and the Who’s Afraid of Virginia Woolf era was about to begin.

Gordon Brown v Tony Blair (Image: PA)

Everything that happened after that, from initial allegations against Mr Salmond to his being cleared of all charges and the subsequent inquiries, will no doubt be gone over in Salmond and Sturgeon: A Troubled Union.

While it will be fascinating to hear from some of the dramatis personae at the time, Liz Lloyd, Ms Sturgeon’s ex-chief of staff among them, the interviews with the “stars” of the show could be the high points.

Yet what can they add to our understanding of events that have been pored over so many times? Mr Salmond and Ms Sturgeon’s public utterances about each other speak to the deep, continuing hurt on both sides. At the Edinburgh Fringe last year, Mr Salmond said “never say never” on the chances of the pair being reconciled one day. She has said there is no going back.

At the same event, Mr Salmond said his successor had “more immediate things to worry about” than them talking again. Quite so. Last year she was arrested, questioned and released without charge pending further investigation as part of an ongoing Police Scotland inquiry. Her husband, Peter Murrell, the former SNP chief executive, has been charged in connection with alleged embezzlement of SNP funds.

Ms Sturgeon’s most recent public appearance was as a pundit on ITV1’s election night show. Her former boss was a guest on Iain Dale’s All Talk podcast at the Fringe a week ago.

An exact broadcast date for Salmond and Sturgeon: A Troubled Union has yet to be announced, with BBC Scotland saying the two-part series will air “in the run-up to” the indyref anniversary on 18 September.

As for where the Salmond-Sturgeon story goes next, keep watching the stars for written updates.