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.
Wuthering Heights (1951 opera) Wuthering Heights is the sole opera written by Bernard Herrmann. He worked on it from 1943 to 1951. It is cast in a prologue, 4 acts, and an epilogue that repeats the music of the prologue. The opera was recorded in full by the composer in 1966, but it had to wait until April 2011, the centenary of the composer's birth, for a complete theatrical performance (there was an abridged stage production in 1982 and a concert version in 2010).