Constantine, Beroe, Massimiano, members of the imperial household, Licinia and the maids arrive. The Emperor is suspicious seeing the son prostrated before his wife. When she explains that he was professing his love for her, all are aghast and even Beroe believes he is guilty. The Empress whispers to Crispo that she is willing to recant and die if he loves her. Massimiano is overjoyed because the turn of events is very favourable to his plans to topple Constantine who is determined to exile the son. Crispo, in turn, blames Fausta for the curse the father has cast on him; she begins to see the early signs of the great tragedy she has unleashed.