The opera's overture and first act were composed by Jean-Baptiste Lully, who died from a conducting injury before he could complete the score.

The end of Act IV, the wedding scene, does contain a vibrant ensemble number at its close which would be more in keeping with a typical finale of one of Lully's operas.

Melpomene replies that the king (i.e. Louis XIV), in his desire for conquest, has plunged the country into war and ignored the Muses and their feasts.

The Muses agree to pay careful attention to the forthcoming play and to try especially hard to enjoy it despite their misgivings.

In a rousing aria ("Je cours asseurer ma memoire"), Patrocle declares that he will defeat Hector.

After Patrocle exits, Achille, left alone, entreats the gods to protect his friend in a moving soliloquy.

Achille swears vengeance on Hector in an impassioned aria ("Manes de ce Guerrier, dont je pleure le sort").

King Priam of Troy, his daughter Polixene and his daughter-in-law Andromaque conspire to soften Achille's heart.

But it is the beautiful Polixene who breaks Achille's heart with her moving aria, "Vous le sçavez, Dieux que j'atteste!"

Achille confesses his love for Polixene to Arcas, who reminds the hero that his original intent was to avenge their dead friend Patrocle.

Andromaque, recognizing Polixene's despair, tries to comfort the bride-to-be, swearing "I will make my fidelity [to you] as famous as his [Achille's] glory."

Priam enters before the troops of Greeks and Trojans and commands that everyone, for the sake of peace, should surrender himself to love.

Polixene sends everyone away, and, in "C'en est fait," a grief-stricken soliloquy, declares that she is unable to live without her husband.