The book opens with Achilles looking out onto the sea, listening for the voice of his mother. Even though he knows he belongs to the Earth, that he has farmed it, and that he will eventually return to dust in it, he still feels attached to the water, remembering the different names he would have for the sea as he called to his mother. It reminds him of how when he was a child, his mother had to give him up so he could become his father’s son—a mortal who lived in the rough, earthy world of men. It has been nine years since they went to war: something Achilles views as unnatural, as war should end swiftly, so one can return home, to notice how much a child has grown, as Achilles has been unable to do for his own son. As the sun rises, he stumbles across the shore of the beach back towards the camp. He looks back at the sea longingly, but he knows the fight will end on the land. Nevertheless, part of him resists, and so he goes out onto the beach every morning, accompanied by his ghosts: Patroclus and Hector.
A flashback begins. Patroclus and Achilles meet one day in Achilles’s father’s court, as a ten-year-old Achilles bursts in on a court session, proud of his successful hunt. His father is hosting Menoetius, King of Opus, who tells him that the boy he brought along with him (Patroclus) is his son, for whom he requests asylum. Patroclus had killed one of his companions in a fight over a game of knucklebones; Achilles’s father accepts and Patroclus becomes a part of the household.
Patroclus becomes essential to Achilles’s life, the piece that he was always missing. There is nothing he does not share with them. Despite this, there are still moments where Patroclus withdraws, aware of his status as an outcast and a courtier to Achilles’s prince. In a strange way, Achilles, too, is involved in the moment where Patroclus kills his companion: in that moment, both Achilles and the deceased companion became bound to Patroclus forever.
The flashback continues in the more recent present, where a war has been going on for years, with a recent resumption of the fighting after weeks of truce. The Greeks are desperate, and so is Patroclus, who, along with the rest of Achilles’s troops, is banned from fighting because of the conflict between Achilles and Agamemnon. The fight is a result of the fact that after Agamemnon’s captive, Chryseis, is ransomed and returned to Troy, Agamemnon demands that Achilles gives up his own slave girl, Briseis, to him. Achilles views this as an enormous insult, and draws himself and his troops away from the fighting. This has been going on for weeks when Patroclus becomes frustrated. He and Achilles fight. Achilles tells him to go save the Greeks himself if he’s so passionate about this, to which Patroclus replies that he will. This upsets Achilles, but Patroclus insists and asks him if he can lead the Myrmidons (Achilles' men) into battle. Achilles feels strange about it, but consents. His brief relief is soon disrupted when he begins to hear the cry of “Achilles!” go up amongst the assembled Greeks, and he rushes to the battlefield, only to see Patroclus killed by Hector.
Achilles weeps unrestrainedly over losing Patroclus, full of anguish. Two days later, Patroclus’s ghost comes to him and tells him to let him go and to bury his body properly so they can both move on. Achilles builds a pyre, and promises Patroclus that he will join him soon, but first, he must have revenge. Hector wears the armor he took from Patroclus’ body when he confronts Achilles, and when Achilles kills him, it almost seems like his own death. He shoves the sword into Hector’s body and Hector grips it as he takes his final breaths. Hector leans close to Achilles as he is dying, and the gods whisper through his voice to tell Achilles that he will not outlive Hector by much.
At that moment, a part of Achilles' spirit leaves him, and he stands motionless for a moment, before bending down to slash Hector’s feet and tie them together with an oxhide thong. He drags the corpse to his chariot, loops the thong around the axle bar, leaps onto the platform, and begins to drive. He drives Hector’s body up and down the walls of Troy as Hector’s family looks on, but he feels nothing. He waits for the rage to fill him, so it can account for the crime he is committing and so it can replace the grief.
The flashback ends. Achilles arrives at the outskirts of the camp, where people have begun the day’s work. He looks among his men, who are hardworking and familiar. They love him unconditionally but they are confused by his behavior and believe he must be mad, because he breaks all convention. When he orders them to lead out his horses, they obey but don’t meet his eyes, because they know what he’s about to do. He attaches his horses, Xanthus and Balius, to his chariot and goes out to where Hector’s corpse lays, and sees that the gods have again defied him by restoring Hector’s body from the abuse Achilles had laid on it the day previously.
Furious, Achilles ties the body to the chariot and drives out onto the plain again. He has built Patroclus a pyre in his grief, slaughtered sheep, cattle, horses, dogs, and prisoners to honor him, but it has not been enough to calm his grief. He drives Hector around the pyre, but is tormented by the fact that it is still not enough. He returns the horses to the stable as his men look on in disapproval, and then goes back to sleep.
He is known as Achilles the Runner among the Greeks, but that runner spirit is no longer with him, replaced by a heaviness of spirit that he associates with the earth instead of his more natural element, the sea. He waits for a break, something to disrupt it.
The tension between the land and the sea for Achilles is a tension between parents, and between mortality and divinity. Though Malouf doesn't mention it directly, Achilles is a demigod, with a mortal father who is the king of Thessalonia and a mother, Thetis, who is a sea goddess. Because he is still mortal, he must align himself with the earth and other humans, but at the same time, he feels an attachment to the sea because of his mother. This in-betweeness is something that defines Achilles' story. Achilles longs for something different: to be a farmer who doesn't concern himself with death, but the war has already determined his fate. Nevertheless, by staying on the beach, Achilles tries to remain as close to his mother as possible. But even when trying to be close with his mother, death follows him in the form of the ghosts of Hector and Patroclus.
Achilles' relationship with Patroclus has the nature of what we might now call codependency. Ironically, what makes their friendship possible is the death of another child—the bond that Achilles senses as a result of this speaks to how much death is what forms the bonds that define Achilles' life. His relationship with his father and estrangement from his mother happen because of the fact that he will eventually die, and dying is what brings him and Patroclus together. Patroclus is a foil to Achilles, almost a less-privileged brother, but that doesn't prevent Achilles from loving him.
In the end, Achilles' love for Patroclus, as well as his pride, is what dooms Patroclus. Because he loves Patroclus and yet is too proud to fight himself after Agamemnon's insult, he allows Patroclus to face Hector, who targets Patroclus specifically because he is dressed in Achilles' armor. His unspeakable grief after Patroclus dies, however, demonstrates how much his love for Patroclus outweighs any pride he has about being seen as weak or incapable. Instead, he focuses solely on revenge.
If Patroclus is a foil, then Hector is Achilles' doppelganger. For most of the war, these two men have been equally beloved by their troops and pretty much equally matched in skill. Seeing Hector wearing Achilles' armor intensifies this effect, so much so that even Achilles begins to feel as if he's killing himself. By killing Hector in Achilles' own armor, Achilles also has the opportunity to assuage some guilt about his own part in Patroclus' death, almost as if he himself is also being punished for Patroclus' death. This is again amplified by Hector's prophecy that soon, Achilles will also die, making the victory over Hector even more bittersweet.
Without the larger Greek mythological context, it would be difficult to understand exactly how offensive Achilles' choice to drag Hector behind his chariot is. In almost all cultures, it is considered abhorrent to disrespect dead bodies, but the ancient Greeks and neighboring civilizations placed especially high emphasis on the proper preparation before burial, viewing it as something that was literally sacred. For them, unless someone's body was prepared and coins laid on the eyes, the soul couldn't make its way in the afterlife. So what Achilles is doing is an affront to the gods as well as being cruel.
This is the reason why Hector's body never stays damaged: the gods are preserving it. However, they're also limited in how much they can interfere, which means that they can't prevent Achilles from trying to destroy each day. The book begins, therefore, on an impasse between Achilles' furious grief and what the Greeks consider to be common decency. Just like Achilles is waiting for a break, we as readers have been positioned to wait for an event to shake things up.