Not much in the extraordinary history of the Church has been weirder than the election of Pope Francis six months ago.For a start, it followed in the wake of Pope Benedict's all-but-unheard-of abdication.
Then we were greeted with the spectacle of an Argentinian who not only liked jumping on buses and paying hotel bills in person but someone who was also an improvised baby-kissing up-close-and-personal type who had taken the unprecedented step of adopting the name of arguably the greatest saint in the history of Christendom, the guy who talked to the birds and embraced Lady Poverty.
No sooner was Francis elected than there were accusations he had been tainted by the regime.
It does seem true, in fact, going on Paul Vallely's admirably organised quickie of a biography, that as head of the Argentinian Jesuits, Francis had censured two Jesuits, Orlando Yorio and Franz Jalics, and told them they had to stop their liberation theology style work in the slums of Buenos Aires.
They defied him and they were subsequently (in 1976) arbitrarily arrested by military thugs and tortured. Francis did not, of course, instigate this but his authoritarian opposition to these priests of the left would not have helped and may have influenced the thugs.
It is also true, however that Francis - who had been close to the Iron Band faction of Peronism - and who as a high-flying Jesuit was not sympathetic to the preferred option for the poor, has changed his tune entirely. He became a prelate for the poor. He went into the slums he forbade his priests to work in. He has kissed the feet of people in jail with AIDS, he has divested himself of every trapping of pomp and glory.
At the beginning of Pope Francis: Untying the Knots we hear the title comes from Our Lady of Augsburg, the figure of the Virgin Mary who could solve the insoluble and who has become the favourite icon of Francis.
It seems clear already he is one of the more radical and populist figures ever to occupy the chair of St Peter. He doesn't, to begin with, give much of a damn about sexual irregularities; he's orthodox theologically but says things like who's he to judge the gays?
And he seems to have internalised as his deepest intimation of the face of Christ the holiness of poverty. There was a reunion, late in the piece, between Francis and one of the men who may have been imprisoned and tortured because of him. The two priests embraced, they seem to have broken down and wept.
Still, he seems to represent the point where the ghost of the spirit of poverty (the liberation dream) goes mainstream.
It could be no small thing for a pope to have suffered his own Gethsemane and recognition in the slime and quicksand of third world iniquity.
He is said to be a brilliant administrator so he is liable to clean up the Vatican male prostitution and the - rather more disturbing - nepotism that sent poor Benedict reeling.
This is as good a preview as we're likely to get because of its compassionate and sensitive attention to the shades and spectres of the past.