The drama opens with the indignation of Agrippina, at receiving her son's orders from Anicetus to remove from Baiae, and to have her guard taken from her. At this time Otho having conveyed Poppaea from the house of her husband Rufus Crispinus, brings her to Baiae, where he means to conceal her among the croud; or, if his fraud is discovered, to have recourse to the Emperor's authority; but, knowing the lawless temper of Nero, he determines not to have recourse to that expedient, but on the utmost necessity. In the meantime he commits her to the care of Anicetus, whom he takes to be his friend, and in whose age he thinks he may safely confide. Nero is not yet come to Baiae: but Seneca, whom he sends before him, informs Agrippina of the accusation concerning Rubellius Plancus, and desires her to clear herself, which she does briefly; but demands to see her son, who, on his arrival, acquits her of all suspicion, and restores her to her honours. In the meanwhile Anicetus, to whose care Poppaea had been entrusted by Otho, contrives the following plot to ruin Agrippina: He betrays his trust to Otho, and brings Nero, as it were by chance, to the sight of the beautiful Poppaea; the Emperor is immediately struck with her charms, and she, by a feigned resistance, increases his passion; tho', in reality, she is from the first dazzled with the prospect of empire, and forgets Otho: She therefore joins with Anicetus in his design of ruining Agrippina, soon perceiving that it will be for her interest. Otho hearing that the Emperor had seen Poppaea, is much enraged; but not knowing that this interview was obtained thro' the treachery of Anicetus, is readily persuaded by him to see Agrippina in secret, and acquaint her with his fears that her son Nero would marry Poppaea. Agrippina, to support her own power, and to wean the Emperor from the love of Poppaea, gives Otho encouragement, and promises to support him. Anicetus secretly introduces Nero to hear their discourse; who resolves immediately on his mother's death, and, by Anicetus's means, to destroy her by drowning. A solemn feast, in honour of their reconciliation, is to be made; after which she being to go by sea to Bauli, the ship is so contrived as to sink or crush her; she escapes by accident, and returns to Baiae. In this interval Otho has an interview with Poppaea; and being duped a second time by Anicetus and her, determines to fly with her into Greece, by means of a vessel which is to be furnished by Anicetus; but he, pretending to remove Poppaea on board in the night, conveys her to Nero's apartment: She there encourages and determines Nero to banish Otho, and finish the horrid deed he had attempted on his mother. Anicetus undertakes to execute his resolves; and, under pretence of a plot upon the Emperor's life, is sent with a guard to murder Agrippina, who is still at Baiae in imminent fear, and irresolute how to conduct herself. The account of her death, and the Emperor's horrour and fruitless remorse, finishes the drama.