Nicola Sturgeon and Alex Salmond are to give inside accounts into the bitter breakdown of their close political friendship in a new BBC documentary.

The two-part series will be broadcast in the lead up to the 10th anniversary of the independence referendum which was held in September 2014.

Salmond and Sturgeon: A Troubled Union, will feature extensive new interviews with both former First Ministers who will give behind the scenes accounts of key moments during a period of unprecedented electoral success for the SNP, the broadcaster said.

A wide range of prominent figures share their insights into the party’s journey from the isolation of the pre-devolution years into an era when it returned MPs in significant numbers to Westminster and gained control of the Scottish Parliament. 

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Mr Salmond and Ms Sturgeon also speak frankly about the controversies and disagreements which ultimately ended one of the most formidable partnerships in Scottish politics.

The series includes contributions from; First Minister John Swinney: former First Minister, Humza Yousaf: Liz Lloyd, Nicola Sturgeon’s former Chief of Staff: George Osborne, former Chancellor of the Exchequer and Geoff Aberdein, Alex Salmond’s former Chief of Staff. 

The series will chronicle key events in the political careers of both Alex Salmond and Nicola Sturgeon and chart the story of the SNP as it emerged from the fringes of Scottish politics to become the third biggest party in the United Kingdom.

Archive-rich, the series will focus on turning points in the SNP’s fortunes, how it built successful electoral strategies and the tensions which arose in the hierarchy.

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Produced by Firecrest Films for BBC Scotland, the series will air on the BBC Scotland channel and on BBC iPlayer. It is produced and directed by Barry Ronan (The Rise and Fall of Boris Johnson, Italia 90: Four Weeks that Changed the World, Jeremy Kyle: Death on Daytime).

David Harron, Commissioning Editor at BBC Scotland said: ‘We are delighted to be bringing our audience this landmark series exploring the inside story of a remarkable political partnership.  

‘The series features testimony from those who were closely involved as well as candid interviews with Alex Salmond and Nicola Sturgeon themselves and offers both insights into the political intrigue of the era as well as reflections on loyalty and friendship which we hope the audience will find compelling.’

Firecrest Films’ Head of Documentaries, Mick McAvoy said: ‘The Salmond and Sturgeon era is one of the most astonishing and dramatic periods in Britain’s modern history.  

"This series reveals the inside story of a period which saw two political powerhouses, and a close group of friends and advisors, take a fringe party into the mainstream and come within grasp of achieving their dream of an independent Scotland.  

‘This is an emotional tale of ambition, power and broken friendships and it reveals the human cost of devoting your entire life to a political cause.’

Audiences will also have another chance to see Yes/No: Inside the Indyref, the acclaimed three-part documentary telling the story the 2014 Scottish independence referendum. Transmission details of both series will be released in due course.