OPUS DEI has enjoyed an avalanche of lurid publicity in the past year or so.

Thanks largely to The Da Vinci Code, the potboiler by Dan Brown that has sold more than 7 million copies in the UK, the worthy and respectably dull Roman Catholic organisation has found itself accused of dark plots, of harbouring murderous albino monks, of wallowing in masochistic mortifications and more besides.

So strident has the popular attention been that the Vatican felt it had to appoint a cardinal to rebut the book’s inaccuracies — Opus Dei has no monks, albino or otherwise — and many groups have dedicated websites to the topic - see for example, www.life4seekers.co.uk/TheDaVinciCode-resources.htm

Amid the furore, Opus Dei’s spokesman, Jack Valero, seems slightly bemused as he weighs up the suggestion that the media fuss might have done the movement a favour by attracting new recruits.

High time, then, for a book to bring this personal prelature of the Pope, founded in Spain in the 1920s by Josemaría Escrivá, into the light of day. And as chance would have it, we now have two, published in the space of a few weeks: What is Opus Dei? by Noam Friedlander (Conspiracy Books £8.99) and Opus Dei: Secrets and Power Inside the Catholic Church, by the Vatican correspondent John Allen (Penguin, £20).

Remarkably, given the recent publicity, neither author has managed to uncover anything remotely relating to a conspiracy within or involving Opus Dei. The organisation is still vulnerable to the familiar accusations of secrecy, however, but these books make it clear that the silence about its membership could be prompted by fear as much as by conspiracy.

Everyone now knows that Ruth Kelly, the Education Secretary, is a member. Allen states it categorically and Friedlander also explores her affiliation. It is Kelly’s refusal to admit it that prevents Opus Dei from confirming it.

She might have her reasons. One leading Catholic commentator said that if she were to admit it, that would finish her chances of becoming Prime Minister, but that implies a residual anti-Catholic, or at the very least anti-Opus Dei, prejudice in British society which many others would dispute. And indeed there is no reason why she should not keep this issue private, as there is no sign that her affiliation is affecting her public work.

Unlike the Church itself, Opus Dei does in its wisdom recognise that not all those called to “sanctify the world through God’s work”, as its newly sanctified founder put it, are called to celibacy. Supernumerary members such as Kelly can marry, live in the world, have children. They make up 70 per cent of the total. Numeraries, who are celibate, live in Opus Dei centres.

It might be this realistic attitude to human intimacy that has helped to keep this organisation, unlike the mainstream priesthood, free of the sex scandals that have done so much to damage the reputation of the wider Church.

So without sex to focus on, conspiracy theorists have been forced instead to seek out money and power. It has been suggested, for instance, that Opus Dei is fabulously wealthy, richer than General Motors. And as Friedlander reports, it was drawn into the Roberto Calvi banking scandal, being forced to deny any involvement beyond banking with the Banco Ambrosiano.

Since this week the five suspects in the murder of Calvi, nicknamed “God’s banker”, went on trial — more than two decades after his corpse was found hanging from Blackfriars Bridge — conspiracy theorists will be watching the trial to see if Opus Dei, among others, gets a mention.

They could be disappointed. As Allen reports: “Nowhere is the contrast between what the outside world believes about Opus Dei and what Opus Dei believes about itself stronger than on the question of finances.” Because its centres are autonomous, Opus Dei has little idea of its total assets. Allen estimates that, in contrast with General Motors’ worth of about $455 billion, Opus Dei’s assets worldwide would come to little more than $2.8 billion — rather less than the $110 billion assets of the US Catholic Church, for example.

Reporting on the Vatican for many years for CNN, Allen has met dozens if not hundreds of Opus Dei members. “I never came across anything that struck me as conspiratorial or ominous,” he says. “I tried to live in an Opus Dei centre for a week, to follow the programme of a numerary. I lasted a day and a half.”

And yes, he did try on the cilice, the spiked chain worn on the upper thigh for two hours each day. It did not draw blood, he says, and was uncomfortable only when sitting down. He points out that the nuns who make Opus Dei’s one-chain cilices take orders for many different religious groups in Italy for cilices with two or three chains of spikes. He confesses that he would prefer the cilice as a discipline to the “lesser” mortifications practised by most religious orders in Britain, such as fasting.

Friedlander, who dedicated her book to her late father, Rabbi Albert Friedlander, a regular Times writer and a “believer in faith and religious tolerance”, emerged thinking that the organisation was much better than she had been led to believe. Like Allen, she says: “I did not meet any murderous monks. Monks are not even part of the organisation.”

It would seem that The Da Vinci Code is really just fiction, that Opus Dei is a lot less interesting and a lot more worthy than has so far been portrayed.

Maybe the simple concept of getting on with our work, or God’s work, as best we can is not such a bad idea after all, something only a saint could succeed in making a way of life for so many.