Erwin Schrott's dressing room is a-buzz. In walks a fellow Uruguayan to exchange fraternal greetings, then a dancer to collect his motorbike boots. Then a soprano comes in and parks her sleeping infant in a corner of the room: this is Anna Netrebko, Schrott's other half, about to open in Covent Garden's Manon: their son Tiago Arua is not quite two.
Shaven-headed and adorned with a feminine little earring, bass-baritone Schrott comes across like the beefy young Brando in Kowalski mode: his charm is very much of the coercive kind, and his Figaro – to be seen on BBC Four tonight, and for real from Monday – has memorable force. Meanwhile his parallel career as a tango singer is just taking off. This has been as much a surprise to him as to everybody else: it began as an encore at a concert in Munich two years ago, where, once he'd started singing tangos, they wouldn't let him stop.
"This music is all my childhood," he says with shining eyes. "My mother and father were dancing tangos all day long. It's the whole of me." Those who heard him singing tangos on Radio 3's In Tune were knocked out by his Latin warmth.
In New York he has now assembled what he claims is the best tango ensemble in the world – the pianist used to play with Astor Piazzolla: "I can't believe how lucky I am to have found them. Most of them are Argentinian, but it's a perfect fusion of cultures. My next CD will be with them – and you won't believe how many opera houses now want to put us on. There are no musical boundaries any more." He's excited but Tiago Arua, tucked up in his corner, sleeps serenely on.
'The Marriage of Figaro', BBC4, tonight, 7.30pm; Royal Opera House, 31 May to 3 July in rep (roh.org.uk)