In Here are the Young Men (2014), Rob Doyle’s debut novel, a drug dealer called Scag, a drunk teenager and two Scandinavian backpackers are sitting in a Dublin pub discussing Knut Hamsun. ‘Do yis know him?’ asks the drug dealer.

‘He wrote Hunger. It’s a book about my life story; this lad comes to a foreign city and does fuck all, and he has no money and goes round the bend a bit. It’s a great book.’

Here are the Young Men is about how young men abandon their lives, stitching all-night benders into panic attacks, getting addicted to drugs and grief. In that novel and his subsequent story collection, This is the Ritual, Doyle outlines a world of mental terror, where sex is traumatic, pornography more so and literature arguably worse than both.

Scag’s summary of Hunger might be a description of Doyle’s latest, the novel-cum-memoir Threshold. The conceit is this: the narrator, Rob Doyle, is a literary hell-raiser set hard against the grain who spends his youth living in cities across Europe, reading, imbibing and failing to write a book.

Even in the