Její pastorkyňa (Her Stepdaughter; commonly known as Jenůfa ()) is an opera in three acts by Leoš Janáček to a Czech libretto by the composer, based on the play Její pastorkyňa by Gabriela Preissová. It was first performed at the National Theatre, Brno on 21 January 1904. Composed between 1896 and 1902, it is among the first operas written in prose. The first of Janáček's operas in which his distinctive voice can clearly be heard, it is a grim story of infanticide and redemption. Like the playwright's original work, it is known for its unsentimental realism.
https://en.wikipedia.org/wiki/Jen%C5%AFfa