The poem begins at the feast that Alexander the Great gives after he defeats the Persian army and captures Persepolis. A bard named Timotheus accompanies the event with a musical performance. He begins with a song that glorifies Alexander and inflates the monarch's sense of pride. The bard then invokes Bacchus, the god of wine and festivities, encouraging the king to drink. Afterwards, Timotheus shifts to a sadder tune, and sings about the dead Persian king Darius. He praises the beauty of Thais, who is portrayed as Alexander’s lover, and encourages the king to be grateful for the relationship he has with her. At last, Timotheus sings of vengeance, which causes Alexander and Thais to set fire to Persepolis. The poem closes as the speaker compares Timotheus to the Catholic martyr St. Cecilia, who similarly moved the hearts of her listeners with her musical performance.