Book 18 of the Iliad opens with one of the most terrible moments in the classics. Here, the hero Achilles learns that his best-loved comrade, Patroclus, has been killed by the Trojan prince Hector. Robert Fagles’ definitive contemporary translation lays out the starkness of his grief: “Both hands clawing the ground for soot and filth / he poured it over his head, fouled his handsome face / and black ashes settled on to his fresh clean war-shirt. / Overpowered in all his power, sprawled in the dust / Achilles lay there, fallen ..."

“Now forward on your hands and thrust your face into the filth," gurgles Christopher Logue’s spectacular punk adaptation of the Iliad, War Music, at this point. “Push filth into your open eyes, and howling, howling / Sprawled howling, howling, in the filth / Ripping out locks of your long redcurrant-coloured hair / Trowel up its dogshit with your mouth."

The lover: Achilles Discovered by Ulysses , a work by artist Jan de Bray. Wikimedia Commons

It seems redundant at this point to make assumptions about their relationship. Yet, the question of whether Achilles and Patroclus were lovers has been disputed for well over two millennia, sometimes as an inquiry into the nature of love itself, sometimes at the simple level of “So, were they doing it?" Plato breezily assumes yes; Bernard Knox says no; Wolfgang Petersen’s Hollywood adaptation Troy debases their bond into a joyless family obligation between cousins, leading the word “cousins" to become an Internet meme, signifying a wilful blindness to the obvious.

Madeline Miller says yes, and goes one step further. In The Song of Achilles, she recasts their lives as the basis for a tender love story between a hero and an ordinary boy, cast in his path like a leaf on the wind.

Juxtaposing myth, classical allusion and textual evidence from the epics themselves, Miller meticulously recreates the childhood of Patroclus, who is sent away from his father’s kingdom to distant Phthia. Achilles, the offspring of the sea goddess Thetis and the Phthian king Peleus, is only a year older than the shy, sensitive Patroclus. They become fast friends, and eventually lovers. They survive several pitfalls, but the divine bargain—early death, immortal glory—which guides Achilles to the Trojan War overcomes them so completely that it is Patroclus who dies first, clad in his lover’s armour, as he tries to trick the Trojans into believing that he is Achilles.

Actor Brad Pitt in Troy. AFP

Patroclus’ niceness is less anachronistic; even Homer sings of him as “the best of the Myrmidons" for his compassion and his calming influence on his famous friend. He is a bad soldier, in Miller’s story, but a talented surgeon, a fledgling diplomat and a loving man, perhaps more contemporary to our time than to Bronze Age Greece.

His is the voice of the novel, a softly erotic murmur filled with hope and fear, even-tempered but rich with narrative power. Through him, we watch Achilles grow to meet each challenge of fortune, and then descend into destructive madness. “Name one hero who was happy," Achilles demands of him at an early stage of the novel. In spite of our knowing the end of their story, Patroclus’ voice keeps us on edge, waiting to see if Achilles will turn out to be the exception.

The Song of Achilles: Bloomsbury, 352 pages, £18.99 (around 1,500).

Trying to explain them in prose is like reading out a line of song. But perhaps Miller’s intention is to do exactly that; to unravel the spell of the epic so that we may hear its meanings better when we return to it. The Iliad accommodates as many readings as we can invent for it. A new book of poetry by Alice Oswald, for example, retells the poem from the perspective of the ordinary soldiers at Troy, rather than the heroes—proving that even a fundamentally hierarchical narrative about divine fate need not be resistant to democratisation, after all.

To say the Iliad glorifies war is like saying the average soap opera glorifies marriage. For the Homeric audience, war is a way of life, and poetry a way to live with it. Its lamentations make it plain that violence can make a human being a thing (to paraphrase Simone Weil). For all its weirdly flattening effects, The Song of Achilles is a sentimental act, of salvaging humanity from that violence. It’s both ironic and affecting that Miller saves a love that ravaged an empire.