Ms Jackson is running on an anti-Blair ticket: it’s as simple, and as complicated, as that.

Among the most awkward of Labour’s Awkward Squad, she insists that the best way of giving the Prime Minister a black eye would be to vote for rebels, like her, who disagree with and dislike him. Got that? Re-elect the Labour MP for Hampstead & Highgate, contribute to Labour’s majority, and undermine the future Labour Government.

I suggest (tentatively, for these actresses can be touchy) that it must feel slightly odd to be running as a candidate for the Labour Party, while vigorously, furiously opposed to the man who heads it. Ms Jackson explodes, with such melodrama that the Saturday morning patrons of Café Mozart look up, startled, from their patisseries. “Excuse me! I have been a supporter of the Labour Party far longer than he’s been on this earth.

“Leaders come and leaders go. The basic principles of the party have been around a lot longer than Tony Blair. This isn’t a presidential election; you don’t vote for Blair, you vote for Jackson.”

This slightly weird rationalisation is what the left-of-centre opponents of the war in Hampstead & Highgate want to hear. It allows them to vote Labour, while continuing to loathe the Prime Minister. They can feel both righteous and indignant simultaneously; have their patisserie and eat it.

Ms Jackson is so far outside the party mainstream that, as of last Friday, she had not even bothered to read the Labour manifesto. Mr Blair’s war is the overriding issue, and one that seems likely to return Ms Jackson with an increased majority.

“I think the result will be very close. Perhaps a Labour majority of between 50 and 70 seats,” Ms Jackson says. Her vulpine grin suggests how very much she would relish that result: as part of a reduced majority, she and other rebels would be able to stamp their influence on a weakened government.

Brittle, and spiny as a sea urchin, the former actress seems poised, and pointed, and more or less permanently peeved. Even with a pint of latte inside her, she carries an air of chilliness. Like many thespians, she seems impatient, and happiest in monologue. Yet she has a reputation as a hard-working constituency MP, and her local popularity is obvious, not least because she has provided Labour voters with a way though an electoral conundrum. Vote Glenda: Bash Blair.

“Of course I’ll vote Labour, but not as enthusiastically,” Matthew Devereaux says, clutching his copy of The Guardian with one hand and Ms Jackson with the other. “It’s like making a marriage work: it may not be perfect, but it’s better than a divorce.”

Ms Jackson won her first Oscar for Women in Love, in which she played the mandestroyer, Gudrun Brangwen. Back then, in 1969, the critic Penelope Mortimer wrote of her performance: “Every movement expresses the passionate longing of a frigid woman for freedom and domination.”

If she wins here, and enough other Labour candidates lose, then Ms Jackson may get the political role one suspects she has long coveted: freedom from party control, and the opportunity to dominate.

HAMPSTEAD & HIGHGATE

MP: Glenda Jackson since 1992
2001 result: Lab 16,601; C 8,725; Lib Dem 7,273; Green 1,654; Soc Alliance 559; UKIP 316. Majority: 7,876

OTHER CANDIDATES

Sian Berry (Green); Ed Fordham (Lib Dem); Magnus Nielsen (UKIP); Piers Wauchope (C); Rainbow George Weiss (vote for yourself rainbow dream ticket)

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