When listening to this opera it is important to remember that in the 17th century men often sang women’s parts and women sang men’s parts. A part such as Nero would have been sung by a castrato. Nowadays it can either be sung by a countertenor (a man) or a mezzo-soprano (a woman). There are scenes in this opera where the actors disguise themselves as the opposite sex. In the 17th century opera audiences did not find anything unusual about a man pretending to be a woman pretending to be a man or the other way round.