Before meeting with Emma Matthews after a rehearsal for Richard Mills’ The Love of the Nightingale, I loiter in the cafeteria backstage at the Sydney Opera House for some time while she removes her stage makeup. It’s a normal part of any opera singer’s routine, but in this case, she explains, it can feel like something far more distressing.

“I remember during rehearsals the last time I sang Philomele, in 2007, I was in the shower for half an hour afterwards washing all the blood off myself and crying. It was horrific.”

The soprano is bright and bubbly as ever when I speak with her in Joan Sutherland’s old dressing room, but it’s clear that this challenging role in the Opera Australia production opening this week has given her a lot to get off her chest. Mills’ third opera takes as its subject the Greek tragedy of Philomele in Ovid’s Metamorphoses; the princess of Athens endures rape and imprisonment at the hands of her brother-in-law Tereus, who savagely cuts out her tongue to silence her. Philomele and her sister Procne exact their terrible revenge by killing Tereus’s young son.

As a mother, Matthews is...