The two short operas Eine Florentinische Tragödie and Herzog Blaubarts Burg are linked by a central theme: the progressive recognition of the only seemingly familiar counterpart. In Zemlinsky's Eine Florentinische Tragödie, the murder of Bianca's lover by her jealous husband Simone leads to a dialog between the two spouses that surprisingly signals a new beginning of love. In Bartók's one-act opera, however, Judith's journey to the inner depths of her beloved Duke Bluebeard - symbolized by the opening of seven mysterious doors - ends in darkness and loneliness.