In the final act, Fiora's body is laid in a crypt, and the people of Altura mourn for her. Archibaldo has secretly poisoned Fiora's lips, so that her lover will die.
In the final scene, Fiora's body is placed in a tomb, and the people of Altura grieve her loss. Unbeknownst to them, Archibaldo has covertly poisoned Fiora's lips, ensuring that her beloved will perish.