Does Werther or War and Peace have more acts?
War and Peace (opera) War and Peace (Op. 91) (Russian: Война и мир , "Voyna i mir") is an opera in two parts (an Epigraph and 13 scenes), sometimes arranged as five acts, by Sergei Prokofiev to a Russian libretto by the composer and Mira Mendelson, based on the novel "War and Peace" by Leo Tolstoy. Although Tolstoy's work is classified as a novel, the 1812 invasion of Russia by the French was based on real-life events, and some real-life people appear as characters in both the novel and the opera, e.g. Prince Mikhail Kutuzov and Napoleon Bonaparte.
The Canterville Ghost (Knaifel opera) The Canterville Ghost (also "The Ghost of Canterville", Russian: "Кантервильское привидение" – Kantervíl’skoye privedénie, however usually spelt as "Кентервильское привидение" – Kentervíl’skoye prividénie; French: Le fantôme de Canterville, German: Das Gespenst von Canterville), an opera by the Russian composer Alexander Knaifel (Russian: Кнайфель) in three acts for 18 singers and chamber orchestra, also in an abridged version for two soloists and chamber orchestra.