The prose is plenty purple in Patrick Roscoe’s The Indivisible Heart, which is just how the author and his diegetic mouthpiece want it. But it would be a mistake to suggest that the protagonist of this slim, beguiling book is oblivious to his floridity, any more than his creator is. Employing the time-honoured tradition of the unreliable narrator, Roscoe’s novel plays games of concealment and misdirection, which in turn reflect the sadomasochistic dynamic at the heart of the narrative.

“Again I’ve been sent out into the demanding night to find what you need,” begins our primary storyteller, a nameless man of about 35. Addressing his thoughts to his lover, he is also entreating the reader: we become the “you” he regards with increasingly poetic reverence. The object of his reconnaissance mission is a young boy, to be procured and delivered for a series of sexual adventures; gradually, it’s revealed that this is a quarterly ritual practised in all the great cities of Europe, and that the narrator both delights and sorrows in his role. He has served his lover in this manner for some 20 years, and sees in his pickups the spitting images of his younger self.

But there’s something else unsettling going on: interspersed amid these reveries are more objective accounts of a grisly crime scene in Seville, featuring an elaborately mutilated corpse whose physical description seems to match that of our protagonist.

The manner in which Roscoe neatly sutures together these two plot strands – and a few other loose ends dangling from the third-person sections – gives The Indivisible Heart a fetching shape to match its descriptions of male bodies kept taut by exercise and discipline. This is a work of unabashed gay eroticism, albeit one in which the threat of violence and death are always close at hand. When one character rapturously equates his scarred body to a meticulously slashed canvas, it seems absurd and yet pathologically plausible: what could be more edifying than to be seen as a work of art?

Roscoe’s finely honed thriller considers the collateral damage of this mindset while finally revealing itself to be about flesh and blood in a different way altogether.