The world premiere of Kaija Saariaho’s Innocencewas the undoubted hit of this year’s Festival d’Aix-en-Provence. The Finnish composer, born 1952, is probably best known for L’Amour de Loin(2000), a haunting medieval meditation on love and loss as ephemeral as incense, yet once heard never forgotten. In her latest opera, however, she deploys her considerable craft to create something very much in the here and now, a topical work that is raw, uncompromising and utterly gripping.

Innocence Lucy Shelton (top), with Beate Mordal, Julie Hega, Simon Kluth, Camilo Delgado Díaz and Marina Dumont. All photos © Jean-Louis Fernandez/Festival d’Aix-en-Provence

Part Scandi-noir thriller, part Ancient Greek drama, Innocencemakes for persuasive music theatre, thanks to Saariaho’s inexorable, multi-layered score and a spellbinding libretto by Finnish-Estonian novelist Sofi Oksanen that has more layers than the proverbial onion. Masterfully helmed by Australian director Simon Stone, it’s as theatrically mesmerising as it is emotionally harrowing.

It begins with a suspiciously subdued wedding taking place in an architecturally clinical hotel in Helsinki. The Finnish bridegroom is marrying a Romanian immigrant whose...