Nisus and Euryalus are two Trojan warriors, inseparable companions, who in Book 9 leave the besieged camp by night to bring Aeneas word of the siege and die together: Euryalus by the sword of Volscens, Nisus over his friend's body.
They already appear in the games of Book 5. In the foot race, Nisus, who is in front, slips in the blood of the sacrificed oxen and, fallen, makes Salius trip so that Euryalus may win. The narrator says that he "did not forget Euryalus, did not forget his love." Aeneas gives prizes to everyone to end the contest without condemning anyone.
In Book 9, Nisus sees the Rutulians asleep with wine and asks whether the gods put this ardor into the mind or whether each one makes a god of his own desire. He proposes crossing the lines by a path he knows. Euryalus refuses to stay behind, and Ascanius promises cups, gold, and the arms of Turnus. Euryalus asks only that they look after his mother, who followed him from Troy and whom he leaves without a farewell, because he could not bear her tears. In the Rutulian camp they kill many. Nisus calls for a stop, but Euryalus snatches the helmet of Messapus, and the gleam of the helmet betrays him to Volscens's cavalry.
Nisus returns, hurls two spears in secret and, when Volscens's sword comes down, steps out of the dark: "Me, me, here I am, I did it." He arrives too late. Euryalus falls like a flower cut by the plow, and Nisus kills Volscens and dies on his friend. The narrator promises the two a fame that lasts as long as the Capitol stands, and it is the poem that takes the place of the tomb. Euryalus's mother laments before the walls, and her weeping breaks the spirit of the Trojans. The text does not decide whether the raid was service to Aeneas or a search for glory.