On his way to prison, Adelberto is encountered by Matilda, who tells him he should never have accepted being engaged to her if he really loved Teofane instead. They are joined by Gismonda, who reproaches her son for being defeated in battle by Ottone. Adelberto hopes that he will learn fidelity from Matilda's example, and is led away (Aria: "Lascia, che nel suo viso"). Matilda and Gismonda are both distraught at Adelberto's defeat and imprisonment. Matilda thinks they should beg Ottone for mercy, but Gismonda would prefer that she and her son both be put to death rather than thus abase themselves. Matilda says she will not allow that to happen, Adelberto must be freed (Aria: "Ah! Tu non sai"). When alone, Gismonda admits to herself that she too feels pity for her son and longs to console him in his distress (Aria: "Vieni, o figlio, e mi consola).