Poul Ruders obviously likes operatic dystopias. After the futuristic Handmaid's Tale and the paranoid parable of Kafka's Trial, his latest stage work, introduced this month by the Royal Danish Opera, is set in the most omnipresent of all contemporary dystopias, the US.

Dancer in the Dark is derived from Lars von Trier's 2000 film. Selma, a Czech immigrant (played by Björk on screen), has brought her son Gene to the US in the 1960s to find treatment for the congenital condition that has almost blinded her and will take his sight, too. It's hardly the prosperous land she's expecting, and her trailer-park life of manual labour, earning the money for her son's operation, ends in tragedy – Selma is convicted of murder and sentenced to death, though learns before she is hanged that Gene's sight has been saved.

Von Trier's film lasts 140 minutes; Ruders' one-act version, with a text by Henrik Engelbrecht, is exactly half as long, hardly scratching the surface of the subject matter. It feels like extracts from a work in progress, with the set pieces of Selma's trial and her execution jarring against the profoundly sketchy presentation of the rest of the narrative.

The piece also seems to assume too much knowledge of the film, to which the ironical edge of the score adds little. Ruders's music alternates doomy expressionism with references to Hollywood musicals, but Selma's love of them, an important element in the film, hardly registers, while the use of a sentimental hymn tune for her final aria on death row pushes the ending perilously close to kitsch.

Kasper Holten's production, set in a dowdy church interior, does what's necessary; Michael Schønwandt conducts, and mezzo Ylva Kihlberg makes Selma as sympathetic as she can, but all have a thankless task.

In rep until 27 September. Box office: (45) 33 696 969.