Act III: A tent near Emain. Lavarcham arrives at Conchubor's tent and tries to convince him to give up his pursuit of Deirdre, claiming that she has grown old and lost her beauty. His soldiers arrive and contradict her claims, and he leaves just before Deirdre and Naoise enter. They discuss the possibility of their impending deaths until Conchubor returns. Deirdre nearly convinces him to put aside past grievances and let them live in peace when the sound of a battle between Conchubor's men and Naoise's brothers reaches them. Conchubor and Naoise go to join the fray and Naoise is killed. Fergus and his men arrive, enraged by the king's treachery, and set Emain Macha ablaze. Lavarcham tries to convince Deirdre to flee Ulster, and Conchubor tries to take her to a different castle, but she stays and mourns her dead lover and his brothers. In the end, Deirdre takes Naoise's dagger, stabs herself, and falls into his open grave, leaving Conchubor with nothing.