Nano-opera: Aida

Two princesses love the same army guy. They dance a war for six years in real time, during which six herald trumpeterss (the only heroes of the opera) try valiantly to get a melody going. After the war they sing about it for six more years. He wins the home girl’s hand in marriage but likes the away girl better. They spend six years arguing about whose house to live in, until his ex comes along, tries to get him killed, and then spends three years changing her mind about it. Finally he and the away girl die together for the final three years of singing, while home girl mopes.

Twenty-four years with two melodies, only a few trumpeter heroes, and no elephant. Why is this mess a classic?