Michael’s Blakemore’s marvellously managed and superbly designed (Ashley Martin-Davis) production of Puccini’s Tosca for Welsh National Opera was first seen in Oxford three days after its opening in Cardiff 18 years ago and has returned frequently since. With ‘our’ spring tour from WNO now relocated to Milton Keynes Theatre, the first of its two performances there this week (the second is on Saturday) took place on Tuesday in difficult circumstances.

A printed slip intended for insertion in the programme read: “Owing to the indisposition of Elisabete Matos, the role of Tosca will be sung at this evening’s performance by Naomi Harvey.” The insertion was never made. Understudy Naomi also fell victim to a throat infection. With her last-minute replacement, Anne Williams-King, able to sing the role but not act it, she therefore took to the stage as Floria Tosca while her substitute supplied the character’s voice from the wings.

And supplied it superbly, producing a rich and supple vocal line and showing considerable ‘feel’ for this great role, not least in her delivery of Tosca’s heart-stopping prayer for strength, Vissi d’Arte, amid the dramas of Act II. However odd the arrangement must have seemed to the other singers – and especially to the two involved in much close-up action with the doomed diva – everything looked, and sounded, almost as normal from the stalls.

The two intimates are, of course, Tosca’s painter lover Mario Cavaradossi, who was ably portrayed by tenor Geraint Dodd, and her would-be seducer, the odious hypocrite Baron Scarpia, powerfully presented by baritone Robert Hayward (pictured right). Both are singers of considerable experience, and neither seemed fazed at having to perform with a mime.

Overall, this was a satisfactory if unusual night at the opera, with especially fine work from the WNO’s excellent orchestra, under conductor Simon Phillippo, taking up his baton with the company on this work for the first time.

There is a further performance of Tosca at on Saturday. Tonight, WNO performs Mozart’s The Abduction from the Seraglio. Tel: 0844 871 7652.