The Iliad covers a few weeks of the tenth year of the Trojan War, in which Greeks and Trojans fight before the city. In Book I, the Greek leader Agamemnon takes the captive Briseis from Achilles, and Achilles withdraws from the fighting. His mother, the goddess Thetis, asks Zeus to honor her son, and Zeus assents with a nod that makes Olympus tremble. This is what the poem calls the design of Zeus: "and the design of Zeus was fulfilled."
In Books II to VIII, the armies clash. Paris, the Trojan who took Helen to Troy, and Menelaus, her husband, try to settle the war in a duel, but the goddess Aphrodite rescues Paris and the truce is broken. Diomedes wounds even gods, Hector bids farewell to his wife, Andromache, and their little son, and Zeus, in Book VIII, weighs the fate of the two sides on a golden scale and makes the Greeks flee.
In Books IX to XVII, the Greeks offer gifts to Achilles, which he refuses, and the Trojans reach the ships. Patroclus, Achilles' friend, asks for his armor to frighten the Trojans, drives the fire away from the ships, and is killed by Hector. In Book XVIII, Achilles receives the news, and Thetis obtains new armor for him, including the shield that the poem describes scene by scene.
In Books XIX to XXIV, Achilles ends his wrath against Agamemnon and returns to fight, kills Hector before the walls and drags the body. He holds funeral games for Patroclus and, finally, the aged King Priam goes alone to his tent to ask for his son's body. Achilles returns it, the two weep, and the poem ends with Hector's funeral, before the fall of Troy.