I suppose the great thing about reading John le Carré, especially the Smiley books, is that at no point do you think, "Come on John, lad", bit far-fetched that bit, isn't it? But you think even the ex-spy le Carré himself might struggle with a sense of verisimilitude in the case of Samantha Lewthwaite, or the "White Widow".
Lewthwaite's case is fascinating for many reasons but even if you've encountered it before, to hear the whole tale recounted, as it was in The White Widow: Searching for Samantha (BBC1), one can be left agog all over again.
To recap, Lewthwaite was an Aylesbury girl – your "typical innocent English rose" according to local Lib Dem councillor Raj Khan – who converted to Islam at 17. She met future 7/7 bomber Germaine Lindsay online and then at a Stop the War demonstration in 2002, dropping out of university to marry him. After his suicide bombing, she was initially thought to be unaware of her husband's acitivites, though her account was soon questioned. She then left Britain for South Africa, remarried Kenyan Fahmi Jamal Salim and, later headed to his home country where's she's been accused of playing a key role with al-Shabaab.
As we've seen in the case of the young men who've left the country to fight in Iraq and Syria for Isis, the notion of Britons leaving the country to fight a holy war is fascinating itself. But when it's a white woman with four children, it's manna to public curiosity.
Buoyed by the extreme interest in Lewthwaite in the wake of the Westgate Mall attacks – of which there are no signs she was involved, despite many rumours at the time – the film-maker Adam Wishart had given himself the task of being the Morgan Spurlock to Lewthwaite's Osama bin Laden and asked the question: where in the world is Samantha Lewthwaite?
The answer, perhaps not too surprisingly, given Abbottabad and all that, is probably somewhere behind a high wall covered in barbed wire. They'll find her one day, you suspect – Interpol currently has a red notice out for her arrest. In the meantime, Wishart did as good a job of finding out what she's been doing for the last decade as you could hope.
Mixed in with an actress reading extracts from diaries recovered in 2011 (an odd, but effective touch), Wishart followed her trail to Aylesbury. There he visited an unlikely connection with the early-Nineties hip-hop scene there (many of the rappers, inspired by Malcolm X, converted to Islam and attended London mosques). We also went to Dewsbury, where Lewthwaite's interactions with Mohammad Sidique Khan were explained.
Then it was Johannesburg where Lewthwaite seemed the "model of middle class respectability" and worked in a halal pie factory where she was "in charge of sausage rolls and Cornish pasties" and eventually to Kenya where she lived as Natalie Webb.
Wishart certainly got to edge of darkness here. After he spoke to Makaburi, a radical Mombasa cleric, the interviewee was shot the next day (and soon killed). He also spoke to Simon Davis, the UN investigator who was later murdered in Somalia.
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And even if there's not too much to implicate her specifically in any attacks, Lewthwaite's trail is a bloody one.
The last person she was seen with was her sister-in-law who was married to Musa Dheere, a man who was a lieutenant to Harun Fazul, the leader of the 1998 embassy attacks in East Africa and a confidant of Bin Laden himself.
Sure, there's a few degrees of separation there, but wherever Samantha Lewthwaite is, she's in deep.
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