we can find our way by distinguishing two themes the action seems to follow on the one hand an amorous and political rivalry pits two men who do not know they are brothers against each other at the same time there is an implacable pursuit of vengeance with all its horrible retinue the spectre of the pyre prison and its tortures terror of death in its extreme suffering the drama' s power draws its spectacular effects from the ingredients of the romanticism of horror we are in the same atmosphere as the dramas of victor hugo which verdi had exploited earlier in ernani mille huit cent quarante-quatre and in english gothic novels so popular at that period of the dix-neuf th century