The one commissioned to put Olympio out of the way came across him at Terni, and conscientiously did his work with a poniard, but Marzio's man unfortunately arrived at Naples too late, and found his bird already in the hands of the police.
He was put to the torture, and confessed everything.

His deposition was sent to Rome, whither he shortly afterwards followed it, to be confronted with the accused.

Warrants were immediately issued for the arrest of Giacomo, Bernardo, Lucrezia, and Beatrice; they were at first confined in the Cenci palace under a strong guard, but the proofs against them becoming stronger and stronger, they were removed to the castle of Corte Savella, where they were confronted with Marzio; but they obstinately denied both any complicity in the crime and any knowledge of the assassin.

Beatrice, above all, displayed the greatest assurance, demanding to be the first to be confronted with Marzio; whose mendacity she affirmed with such calm dignity, that he, more than ever smitten by her beauty, determined, since he could not live for her, to save her by his death.

Consequently, he declared all his statements to be false, and asked forgiveness from God and from Beatrice; neither threats nor tortures could make him recant, and he died firm in his denial, under frightful tortures.