Andrew O’Hagan’s “Mayflies” is unrelenting. During the first half of the book where we see a group of Scottish lads on ‘the lash’ in Manchester, he immerses us in their over-the-top hedonistic experience of drink, drugs and music without giving us a chance to come up for air.

Then, in the second half of the novel – a sombre examination of a decline through illness towards an atypical outcome – his approach is the same: we are thrown in the deep end, waves crashing around us, no armbands to help keep us afloat.

The two halves are, of course, in stark contrast to each other in terms of tone.

Although the novel was compelling as a result of this approach, I am not quite sure how to respond to it. As a reader, I was sucked through it remorselessly, and it is easy to see why words like “stunning”, “funny”, “passionate”, “powerful” can be applied to it – and yet I got to the end unable to put my finger on a) just how good it was, and b) whether or not I enjoyed it.

“Mayflies” professes to be a novel about male friendship, but for me this theme – which, like all friendships, probably needs subtle handling – was dwarfed by the rowdy chaos of the first section, and the knee-deep pathos of the second.