If Louis Theroux invited you to be the subject of one of his documentaries, surely the first thing you'd wonder is: "How weird am I, then?" After all, Theroux is a man who picks his prey precisely for their oddball factor. His line-up so far has included a charming assortment of curiosities, from Boers to UFO-hunters, in his Weird Weekend series, and, more recently, Paul Daniels and Debbie McGee, Jimmy Saville, and Neil and Christine Hamilton.
His latest victim, however, the Conservative MP Ann Widdecombe, is still at a loss as to why Theroux asked her. Yet this is the woman who is widely believed to still be a virgin at the age of 54, whose appearance is, to say the least, unorthodox, and who has in the past trained her sights on abortionists, women priests, homosexuals, unmarried mothers, and asylum-seekers (more than 80 per cent of whom are "bogus", remember).
This is the woman who put paid to Michael Howard's chance of becoming Tory leader with the line that he had "something of the night" about him, and who sees nothing strange in writing 1,400 words in a newspaper about the demise of her two cats, or posting a picture of herself on her daffy website – "the Widdy Web" – on the phone with the caption "chicken madras, two naan bread and an onion bhajee".
"I really don't know why he chose me," she says, looking, to me at least, comely with her ash-blonde hair and navy suit. "If you look at the people he's doing – Max Clifford, the Hamiltons – I make a very odd third. Perhaps he was going for a contrast?"
How does she think people see her? "I don't really mind; it's not something that exercises me. Louis asked questions like that. He spent hours trying to analyse things. I don't analyse myself."
Theroux shadowed Widdecombe on and off for three months last summer, during the Tory leadership contest, and then joined her and her mother Rita on a cruise of the Arctic. She had only seen When Louis Met Paul and Debbie, and thought it "perfectly sensible" in that it followed the attempts of the magician's assistant to get a ballet company off the ground. (Most of us, however, will remember it for revealing how considerably more barmy the couple was than we had first suspected.)
The other reason for agreeing, she says, was that: "On the whole, my disposition is to say yes, unless I've got good reason to say no, and I think that's being in public life." Had Ms Widdecombe seen the show featuring the Hamiltons (it hadn't then been screened and she doubts she even knew they were in the series) she admits that she "probably wouldn't have touched the subject with a 10ft bargepole, as I don't think they came well out of it". As it is, it appears Widdecombe made the right decision. She gets the publicity while Theroux reveals little more of his subject than we already know, largely, one suspects, because Widdecombe is too sharp and not sufficiently vain. He fails in his attempts to nose around her bedroom and bathroom. She is "not unhappy" with the end result.
There is, however, the glorious revelation that inside her south-London home, with its fantastically busy curtains and carpets, and spearmint leather sofa, is a considerable teddy-bear plate collection.
One thing does, however, leave the viewer still utterly dumbfounded by the end of the show. Widdecombe actually believed that Theroux would stick to his promise of not bringing up her alleged virginity, which, predictably, he does within the first five minutes. (Widdecombe famously threatened to sue a reporter who suggested to her that she wasn't still a maiden.)
"As you probably realised, there was a huge row off-screen," she says. (There's a pretty enjoyable on-screen humdinger, too.) Did she not realise that it would be the first thing he would bring up, and that, in fact, the surprise was that it took him as long as five minutes to do so?
"I thought we'd agreed even before we'd started that we weren't going to do an interview along those lines. They said 'yes, yes' and were very reassuring – they didn't want that sort of programme blah, blah," says Widdecombe. "Why would they break an agreement?"
To make good television, I say.
"I still operate on the basis of honour," she says, in that adorably strident manner.
As in When Louis Met the Hamiltons, the real star of the show is the mother. Rita, 90, almost lets Theroux into their boudoir on the cruise liner. When he asks whether it's OK with her daughter, Rita announces: "It doesn't matter about Ann." (Widdecombe Jr wades in to stop the invasion.) But more entertaining still is when Rita starts reciting a poem to Theroux that she has made up about Kate, the director/producer. Widdecombe tries to silence her, but Rita continues in pantomime hushed tones, every time Widdecombe looks away.
So what did Widdecombe make of Theroux? "He rather charmingly pretends to be terribly naive, and there was one occasion, not on film, when he seriously tried to persuade me – and this is a guy who read history at Oxford – that he didn't know whether St James's Palace was still standing. I said: 'Louis, you're rumbled'. The fun part was trying to rumble him, when he was doing his silly act."
Christine Hamilton appeared to be smitten with Theroux. Did Widdecombe fancy him? "Certainly not! Not my scene. Come on. And he wouldn't have expected me to, and he wouldn't be hurt by my saying that. That is just not my scene, it's not me," she says, somewhat overstressing the point.
Widdecombe is, however, no stranger to affairs of the heart. Her second novel, An Act of Treachery, out in July, is the story of a French girl who falls in love with a German officer in occupied France. What does she know about romantic love?
"What a cheeky question! You must think you're Louis Theroux. I don't have to answer that question. If I had written a murder mystery, would you ask me what I know about killing people?"
She does admit, though, to having been in love once. The man was Colin Maltby, a fellow-student at Oxford. He was, according to Nicholas Kochan's biography of Widdecombe, "something of an academic nerd, with big glasses, a shambolic dress sense and wild hair: he came from an introverted English family and shared with Ann an awkwardness in personal manners that would draw them together". One contemporary remembered that people made ruthless fun of them. The relationship (they booked separate rooms on holiday together) lasted three years.
Does she regret that it didn't continue? "No, I don't think so, not from this distance, no. He's very happy, I'm very happy." She has often said that Mr Right simply never came along. Would she have liked him to? "It was never a priority. It wasn't that I set my face against it, but equally I never set my face towards it. I've done other things with life, and certainly it's not an active source of regret and never has been."
What if he came along now?
"He will not come along now!" she exclaims. "I'm too set in my ways."
He might like her ways, I suggest.
"I promise you that there comes a time, certainly in middle middle-age and definitely by late middle-age, when you are so set in your ways that you really don't want anybody else interfering with them."
She never feels lonely and gladly shuts her door at night, knowing that only Rita, with whom she lives, will be there. She says, in her precise way, that she probably would rather have had children than not, but doesn't actively regret not doing so.
Her mantra has always been "take me as I am", yet over the past two years, she has turned from being raven-haired (with a badger streak when her roots needed doing) to blonde. "This is the first time in my whole life that I've ever had 100 per cent approbation for a thing that I've done," she says. Her explanation is that she just fancied a change. Her current diet (parliamentary Weight Watchers) does, however, have a considered reason behind it – the onset of varicose veins, lower back pain and raised cholesterol.
Widdecombe admits that people have been extraordinarily cruel about her appearance, for example by dubbing her Doris Karloff. Does she believe that it has hampered her career in any way? "I think it would be quite wrong to suggest that it hasn't played a part," she says. "When it came to whether or not I was going to stand for leadership, there were people – and I know because they told me so – who said they thought I looked rather odd and the public wasn't really ready for that.
"I don't blame it as being the main reason, but some people still like you to look exceptionally smart and conventional – the female equivalent of a pinstriped man."
How did she feel about that?
"I knew it to be the case. If you're in public life, you get inured to it." She didn't do anything about her looks, she says, because they were such a small part of the reason why she didn't stand for the leadership, the more considerable obstacles being her views and the competition.
Sadly, it seems her appearance has never been right for some. One Oxford contemporary, Julian Priestley, now Secretary General of the European Parliament, said: "To be brutally frank, she didn't have a great deal of physical presence ... she wasn't only small in height, she was actually very thin."
Widdecombe plans to do one more parliament if her constituents in Maidstone and The Weald are still up for it, and then retire to Dartmoor where she will walk, have a tribe of animals and write more fiction.
In the meantime, her days will be spent in Westminster, batting away infernal questions about her virginity from journalists. Nights will be spent at home with Rita, who, one suspects, won't be wheeled out in front of the media again, much to our great chagrin.
'When Louis Met Ann' is on BBC 2 tonight at 9pm
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