Observations: To Cannes via 'Cosi'

William Shimell – British opera's answer to George Clooney – turns up to talk about playing the evil genius Don Alfonso in the Covent Garden Cosi fan tutte (which he's currently singing to acclaim), but the score he's nervously clutching is that of Stravinsky's Rake. The singer playing the evil genius in that show is seriously off-colour: if he flakes out, Shimell – a noted exponent of that role, and conveniently on hand – will have to step in. "Do you mind," he asks, "if I keep my mobile on?"

Things have a habit of happening to Shimell. Last summer he was singing in Iranian film-maker Abbas Kiarostami's production of Cosi in Aix, and, in the middle of a rehearsal, Kiarostami suddenly asked if he fancied acting in a film. "Why not?", was his reply (though he'd never done a film before) and lo, the film is now completed, with Juliette Binoche as his co-star, and is tipped for the red carpet at Cannes.

As he speaks his mobile goes off, making him almost jump out of his skin. The dreaded call? No, just his director, Jonathan Miller, wanting a breakfast chat about Cosi. Last week, Shimell adds, Miller had casually asked him if he fancied a role in a play – though he'd never done straight theatre before. His answer had been wary: "I'm happy to breeze in and earn good money in a quick film project. But I live in Cornwall, so a long West End run would destroy my family life." On the other hand, if a film career now beckons, he won't say no. "There's a vogue at present for slightly older men, so perhaps I can catch that wave." Is this his Clooney moment?

'Cosi fan tutte', to 17 February in rep, Royal Opera House, London (roh.org)