20 is an opera in three acts by Erich Wolfgang Korngold, about "the redemptive power of love over injustice and adversity".

A suite for violin and piano based on the music from its famous aria "Ich ging zu ihm" was published by Schott.

Heliane had its world premiere in Hamburg, to critical and public success,[2] and it went on to be performed on 12 stages in the coming years, including Vienna and Berlin.

[3] In 1928 it was presented at the Berlin Städtische Oper under Bruno Walter, where it met with negative reviews from critics who felt the music was not modern.

[2][citation needed] According to Brendan G. Carroll's article in the New Grove, Das Wunder der Heliane is arguably Korngold's greatest opera.

Lotte Lehman stated that her recording of its famous musical sequence, "Ich ging zu ihm", was among her favorites.

In September 2017, a production at Opera Vlaanderen opened, directed by David Bösch and conducted by Alexander Joel with sets and costumes by Christof Hetzer.

The cruel Ruler exercises his power over the land, but suffers because he is unable to win the love of his wife Heliane.

A young Stranger has recently arrived in the land and is bringing the people joy; as a result, he was arrested, sentenced to death, and will be executed at sunrise.

The Ruler dismisses the court and tells Heliane that she will be on trial before God: if she is innocent, as she claims, she must bring the Stranger back to life.

The Judges, together with the Chief Justice, arrive to witness Heliane's attempt to bring the Stranger back to life.

Just as suddenly, stars begin to appear in the sky and everyone is amazed to see the young Stranger's corpse rise, transfigured from the funeral bier.