This is not the age of experimental fiction — it’s Franzen’s, not Foster Wallace’s. That shift was on its cusp in 2007, when the critic James Wood had declared in favour of realism, and Steven Hall published his debut, The Raw Shark Texts. It was a British metafictional novel that created a big splash. Noted for its innovative design, it transformed into a flick book in which a text-block shark menaced the reader.

In the years since its publication, mainstream experimentalism has paled into the cosy, metafiction-lite of Matt Haig, though there’s quality stuff on the fringes — Rob Doyle’s Threshold, for example. Hall has been undeterred by shifting fashions, and his follow-up shares many of the features of his debut. There are blocks of text in the shape of leaves, characters who may not exist, and long discourses on entropy: the titular demon is a conceptual one that briefly appears to break the second law of thermodynamics.

The protagonist is Thomas Quinn, a struggling novelist and the son of a late, famous writer. His wife is away, working on Easter Island, being live-streamed and getting rather too close to a colleague. Lonely and broke in her absence, Quinn receives an intriguing photograph from a former protégé of his father’s, the hugely more successful, and now reclusive, novelist Andrew Black. Soon our hero is on a quest to find Black and steal his valuable new book.

Written in the first person and paced like a thriller, there’s an intimacy and immediacy that quickly grips, and even the long digressions on theory — a trademark of the form — are enjoyable to read.

As it wears on, though, the plot’s improbability jars with its striving for emotional resonance. Far-fetched and relentless twists are fine in a picaresque romp, but less so when we’re expected to care. Also, there are references to Dan Brown that I assume are tongue in cheek, but things do get rather… Dan Brownish.

In the novel’s final pages there’s an interesting, unexpected turn: a literal interpretation of the post-structuralist idea that language creates, rather than merely describes, reality. The problem is that we’re not invested enough in one of the key characters to give it the heft it seeks. A perfect example of this sort of ending — indeed of this sort of book — is Bret Easton Ellis’s Lunar Park,published two years before Hall’s debut. It remains the gold standard.