Clemency, Linbury Studio, London<br/>From the House of the Dead, Grand Theatre, Leeds

James MacMillan's opera weaves the longing for a child with the skewed vision of fundamentalism

Has James MacMillan mellowed? Clemency, his latest opera, introduces the most complex of subjects in the most direct musical language.

The forces are modest (five singers and 24 strings), the score concise, only 45 minutes long. The hectoring ululations of his St John Passion have softened into an unaccompanied melismatic prayer, prelude to a simple meal. There are allusions to Tippett, Britten, even Palestrina, fluency and brightness in the sunburst arpeggios and golden halos of the orchestration. Most surprisingly, there is a hint of revulsion at the strident certainty of the three Angels who visit Abraham and Sarah on their way to raze Sodom and Gomorrah.

Designed by Alex Eales, with a set in the form of a Flemish altarpiece, Katie Mitchell's Royal Opera House/ Scottish Opera co-production has simplicity and gravity. Having collaborated with MacMillan and his librettist, Michael Symons Roberts, on Parthenogenesis and The Sacrifice, she is attuned to their rhythms. The opera opens to ambient sounds – birdsong and aircraft. In one panel of the triptych, Sarah (Janis Kelly) kneads bread. In the second, Abraham (Grant Doyle) counts his earnings. The third is a mirror image of the second, allowing us to witness the dialogue from both sides.

The branches of an oak tree reach through a broken window into the room where Abraham offers food and shelter to three travellers (Andrew Tortise, Eamonn Mulhall and Adam Green). They enter as workmen and leave as assassins, an otherworldly dazzle of righteous triads in rhythmic unison. For certainty, read fundamentalism. The aircraft noise is the first of several references to 9/11. Having repaid Abraham's mitzvah with the miraculous news of Sarah's pregnancy, the triplets fulminate against the sins of the "twin towns". Abraham's pleas for mercy are ignored, leaving Sarah to contemplate motherhood with "gratitude and terror", as well she might, given this baby's future role as putative sacrifice. One life is given, thousands taken. Is this justice?

Under Clark Rundell's calm, clear beat, the Britten Sinfonia realise MacMillan's score with bite, beauty and vigour. Nothing is lost by the lack of percussion, brass and woodwind. In the dry acoustic of the Linbury Studio, the divisi strings had an astonishing gleam, as did the trio of Old Testament hitmen. How much of Sarah's history with Hagar was in Kelly's characterisation? Was that guilt in her face? Jealousy? Mouth twisted into mirthless laughter or wild nausea, she is riveting, despite a challenging tesseratura and lyrics that ape the King James Bible, without matching its poetry. Doyle's Abraham is sympathetic and eloquent from his opening prayer to his futile imprecations. Best ignore the backstory and what later passes between him and Isaac, miracle child.

Retribution is further flayed in From the House of the Dead. Based on Dostoyevsky's memoir of imprisonment in a Siberia gulag, Janácek's last opera is a collage of personal histories. Stained-glass brass, keening woodwind and klezmer strings collide with tawdry tales of vagrancy, deception, murder. Some want to confess, some to justify their crimes. Janácek makes no judgement, but performs the authorial miracle of letting them speak for themselves. Perhaps this is what he meant by finding the "spark of God".

John Fulljames's Opera North production underlines the episodic, confessional nature of the opera. As Skuratov (Alan Oke), Shapkin (Mark Le Brocq), Filka (Jeffrey Lloyd-Roberts) and Shishkov (Robert Hayward) relate and revise their narratives, their words are projected in crude, handwritten letters. Richard Farnes conducts with passion and precision, though the orchestra are slow to warm up. Designed and lit by Dick Bird and Bruno Poet, the prison is a monster that guzzles life and spits death. Dissident Goryanchikov (Richard Morrison) watches in horror as the feast- day pantomime incites brutality that results in the injury of the boy Alyeya (Claire Wild). But the systemic dehumanisation of the mad and bad makes victims of them all. Untidy strings aside, it's a powerful achievement for Opera North, whose male chorus must feel like lifers after this and Fidelio.

'From the House of the Dead' Lowry, Sal- ford (0843 208 6000) Thurs, and tour

Next Week:

Anna Picard hopes for fairy-dust in ENO'S new A Midsummer Night's Dream

Classical Choice

There's a chance to hear a rarity as Cantus Cölln perform Buxtehude's seven-part meditation, Membra Jesu nostri as part of the Lufthansa Festival of Baroque Music at St John's Smith Square, London (Tue). David McVicar's new production of Die Meistersinger opens the Glyndebourne season (from Sat) amid the rolling downs of East Sussex.