“With the third volume,” he declares, with a rueful smile, “I might ruin the whole thing, of course” I suppose he might, but I doubt it. This writer, who has always “felt like a foreign writer in my own language and in my own country”; this writer who lives in Madrid but writes a weekly column in El Pais attacking Spanish culture; this writer who inherited the crown of a legendary kingdom and who keeps the legend – and the joke – alive, has always done exactly what he wants – and he has done it brilliantly “I just do my own thing,” he shrugs. “We think we know people’s faces,” explains Marias, “we think we know more or less what we can expect from them.”My father,” he continues, “suffered a tremendous disappointment, but we have all had disappointments. Sometimes, afterwards, we think, yes, I did see this coming – or yes, I did see it, but I didn’t want to see it. In the middle of a war,” he says, “you can find the very worse behaviours and probably the very best as well. Everyone has his possibilities inside his veins, and it’s a matter of time and it’s a matter of circumstances.

In a way that’s the terrible thing in this book, you don’t even know what you would do.”Marias is half way through the third volume in the trilogy and he doesn’t yet know how it will end. The prediction, that is, of their “face tomorrow”.Dance and Dream is based around a single evening in a nightclub, one that culminates in a violent scene with a sword in a disabled toilet. This being a Marias novel, it also drifts back to memories of the narrator’s failed marriage, conversations with an old friend, the host of the party at Oxford, and with his father. At the heart of the novel is his father’s betrayal by a close friend in the Spanish Civil War, a betrayal Marias’s own father actually experienced. Deza is invited to work for a mysterious group whose activities seem to be based largely on the close observation of people’s character and the prediction of their future behaviour. In Fever and Spear, the narrator, Jacques Deza – yet another Anglophile Spaniard – is approached at a party in Oxford by an enigmatic figure whose occupation remains hazy.

It is hard to think of a more appropriate metaphor for the wafer-thin line between truth and fiction, that “dark back of time”, according to Marias, that “happens only in a sphere that isn’t precisely temporal, a sphere in which writing, or perhaps only fiction, may – who knows – be found.”Marias’s new novel, Dance and Dream, the second in a trilogy with the overall title Your Face Tomorrow (a trilogy that Marias claims is one long novel, published in three parts) continues to explore this theme, this time in the more dramatic fictional context of surveillance and espionage. It was Marias’s obsession with this wild beggar poet that led to the literary wild goose chase that ended, in a series of surreal twists, with his own inheritance of the Redonda crown. Some of the greatest minds in the country were, it seemed, unable to distinguish between fact and fiction. Marias decided to set the matter straight, or at least to pretend to, in a book he playfully called “a novel”, describing the reception of All Souls and the varieties of paranoia it provoked.One of the characters whose fictionality was not questioned was, in fact, real: the “ill-fated, calamitous and jovial writer”, John Gawsworth, whose real name was Terence Fytton Armstrong, but who also bore the splendid title “Juan I of Redonda”. His witty portrayal of a community immersed in one-upmanship and gossip was greeted with an enthusiasm that proved remarkably literal-minded.