Here is a novel that delivers on its title: these variations on a theme do amount to an enigma... As ever, Aciman’s evocation of weather, emotional subtlety and time passing is wonderful. The narrative moves seamlessly into earlier years: the past is the present, the present the past... the pace can be excruciatingly slow, and the lack of any real knowledge of who or what Paul is creates a constant sensation of something missing... The complete lack of attention paid to Paul’s sexual orientation is refreshingly contemporary... The absence of a conventional sense of story or structure reflects the musical form that Aciman is invoking, making this a clever experiment but also a frustrating one. For all its author’s indisputable talents, Enigma Variations creates, deliberately or otherwise, a sense of unfinished business.

Love, unrequited or not, is something of an Aciman speciality, and he returns to it here in his fourth book, Enigma Variations. More of a collection of vignettes than a straightforward novel, it examines the emotional turbulence of the narrator with an exacting, often lyrical eye. The first section is the best, in which Paulo, as a 21-year-old, returns to the Greek island where he spent his childhood holidays. The house has burnt down, symbolising at once destruction and also the possibility of renewal. Throughout the book we see Paulo in a number of different guises, as if he is constantly rebuilding himself, right into middle age...Aciman’s great strength is the delineation of passion, and he is excellent on memory, truth and identity. But when there are quite so many beloveds, it begins to be difficult to believe in the strength or sincerity of Paulo’s claims. Yet, there is an urbane, worldly wisdom here, which charms, and the book urges us to drink the wine of life while we still can.

Enigma Variations returns to familiar themes and settings – the overwhelming power of desire and the vicissitudes of time... In the closing lines, Paul's real life pierces through his solipsism like a savage punchline to a joke. I would have liked more of that throughout the novel but, even so, there is much to savour here.

I should say it’s also an oddly hopeful book, full of tough pleasures. And if you think Aciman has explored this territory before — true, but he’s up to something bolder this time. This book reads as if he’s taken his three previous novels, combined and distilled them down to their essence... He writes with the ferocity of a writer who’s finally getting his vision down, and he has to say it, has to get it out. He’s made a magnificent, living thing.