 The duet between Rigoletto and Sparafucile that opens the second scene of the first act is also unprecedented in its structure, being a free-ranging dialogue with melodies not in the voices but in the orchestra, on a solo cello, solo bass, and low woodwinds to create a distinctive sinister atmosphere.The famous quartet in act three is actually a double duet with each of the characters given a musical identity—the ardent wooing of the Duke, with the main melody, as Maddalena laughingly puts him off, while outside Gilda has a sobbing figure in her vocal line and her father implacably urges revenge.Victor Hugo resented his play, which had been banned in France, being transformed into an Italian opera and considered it plagiarism (there were no copyright restrictions against this at the time).