It's the new PM. Forget Brown. What about Jane?

It looks like fact but it's a BBC drama as Jane Horrocks plays a supermarket manager who storms her way to Downing Street
It sounds so far-fetched it could only be fiction: the tale of a woman supermarket manager who, despairing of all politicians, makes her own bid for Downing Street - and to her amazement - wins.

For now, it is fantasy. But the inspiration behind a new BBC1 drama exploring where public contempt for politics might one day lead is rooted in fact.

Last week Clare Short declared she was too ashamed to stand again as a Labour MP and a survey found that only one in four people thinks politicians tell the truth. The drama is beginning to look, at the very least, timely.

Sally Wainwright, the writer behind The Amazing Mrs Pritchard, hatched the idea at the last general election when she realised she didn't know who to vote for, and nor did many of her friends. 'I felt there was nobody out there saying the things I wanted to hear: it seemed to be all name calling,' she said.

'When I was starting to vote, it was when Margaret Thatcher was coming into power and both extremes [of left and right] were much clearer: politics was so much more exciting, much more involving. People got genuinely angry and upset and desperate.

'Now we are so apathetic: [the last election] was the first time I had got to the point of thinking, "I'm not going to bother voting". I thought instead of being so apathetic, I should stand myself but of course I was never going to do that. And then the thought was, "What if there was somebody who would?"'

Ros Pritchard, played by actress Jane Horrocks, is the motherly manager who erupts in fury after two rival MPs canvassing outside her store get into a fight, and she yells at both of them that she could do better. The brawl hits the news, and so does she, with her argument that professional politicians lie and so it is time for an amateur to have a go. To her surprise, she taps into such a groundswell of anger that she is besieged by other people wanting to stand.

Her employers bankroll her; first the odd Labour backbencher, then frontbenchers, begin defecting to her Purple Alliance. Political advisers pitch in and write her manifesto, and she is propelled into Number 10 at the head of a makeshift army of MPs. The series is about how she copes - not least with the strains on her marriage - and whether she sticks to her original principles.

It might sound too implausible, but Wainwright says she took advice on the feasibility of the plot from Labour MP Andrew Mackinlay and ex-ministers Barbara Roche and Edwina Currie.

That two of her consultants were women may be no accident. Pritchard's cabinet is overwhelmingly female, with a woman Chancellor (Janet McTeer) - who defects to Pritchard in the ladies' loo - and Home Secretary (Geraldine James). As Pritchard tells Newsnight's Kirsty Wark (in a cameo role as herself): 'Women don't muck about with the truth like men do, because women can handle being wrong occasionally.'

It is perhaps no accident that just as real-life politics teeters towards soap opera - Pritchard takes over Number 10 from Tony Blair - political drama is bouncing back. The Amazing Mrs Pritchard, from the same production team, Kudos, behind the spy series Spooks and Life on Mars, is part of a blossoming that includes 'docudramas' such as Harvey Keitel's controversial epic The Path to 9/11, and Peter Morgan's and Stephen Frears's The Deal, imagining how Gordon Brown and Blair reached their leadership pact.

Wainwright says that as recently as last year, when she produced a modern Taming Of the Shrew for the BBC and wanted to set it at Westminster, she was told 'nobody was interested in politics'. Her latest commission suggests the tide is turning, despite BBC sensitivities over fictionalising politics given its duty of impartiality.

Partly to satisfy that duty, Pritchard's politics are kept vague. But 'she's the middle of Middle England, she steals from the left and borrows from the right', said Wainwright. 'I didn't want to associate her too specifically with anyone.'

Although it begins as comedy, the series, which starts on 3 October, becomes progressively darker as Pritchard grapples with tougher issues, such as terrorism. If a second series is commissioned, Wainwright wants to explore whether power ultimately turns her into the kind of politician she stood against.

Her research, the writer said, had taught her mainly 'what a closed world Westminster is. This is one look at what could happen if it radically opened up.'

They could have been contenders

Paul Eddington in Yes, Prime Minister BBC2, 1986

Sequel to Yes, Minister, in which Jim Hacker (Eddington) has a vision of how to run the Department of Administrative Affairs but faces weighty bureaucracy and baffling jargon from his nemesis, the silky smooth civil servant Sir Humphrey Appleby (Nigel Hawthorne). Things don't get much better when the hapless Hacker is somehow installed at Number 10.

Robert Bathurst in My Dad's the Prime Minister BBC1, 2003

The Cold Feet actor plays a Blairite PM in Ian Hislop and Nick Newman's peek into everyday life behind the famous black door. His control freakery counts for nothing when his wife and children constantly shatter the dignity of 'Saddo Daddo'.

Anthony Head in Little Britain BBC3, 2003

Prime Minister Michael is sexually harassed by his clingy, bitchy and insanely jealous aide, Sebastian, played by David Walliams, in a severe case of unrequited lust. Head once said: 'David asked if he could kiss me to make a scene stronger. We puckered up, then he opened his entire mouth and clamped it over my face like a limpet.'

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