When the star soprano stepped onto the Royal Opera House stage at the opening of Puccini's La rondine ('The swallow'), the tension was palpable.
Whatever the rights and wrongs of her tricky week in the press, Angela Gheorghiu fully deserved her roar of applause two hours later for having set aside personal matters and honoured her responsibility to the audience even though she was manifestly out of sorts. It has not always been thus with the Romanian diva.
During Act One of this revival (Nicolas Joël's exquisite production was first seen with Gheorghiu and her then husband, Roberto Alagna, in 2002) the soprano tamed her evident vocal issues, stress-related or otherwise, by subduing her delivery to conceal its lack of bloom and freshness. Her colleagues in the busy salon scene supported her by doing likewise - a generous gesture towards their star but one that put a strain on attentive ears.
La rondine is a night of great tunes in search of an opera. Puccini expressed early doubts about the libretto yet proceeded to set it anyway when he should, arguably, have paid greater heed to his inner voice. Where Tosca (which returns to the Royal Opera this week) gives steak and potatoes, La rondine is a meringue: briefly delicious but little more than a meltaway moment. It suffers most from an implausible final act in which the confident, playful Magda (Gheorghiu) undegoes an inconvenient bout of conscience merely so the evening can end in tears.
Stephen Barlow has revived Joël's staging with true Belle Époque refinement. Ezio Frigerio's sumptuous designs - Art Deco with Art nouveau accoutrements - are a feast for the eye, abetted in Magda's salon by guests who don't so much sit as drape themselves over her furniture with studied ennui. The piano-playing poet Prunier (Edgaras Montvidas) lets a languid cigarette dangle from his lower lip as he ushers in the much-loved aria "Chi il bel sogno di Doretta" amid this company of human antimacassars.
The soporific atmosphere livens up considerably when our hero Ruggero appears. An immediate chemistry between Charles Castronovo and his leading lady helped lift the mood, and the grateful squeeze Gheorghiu gave the American tenor at the final curtain was probably more significant than the embraces shared by their fictional counterparts. Castronovo sang a rhapsodic first aria, Ruggero's hymn to Paris, and carried the energy of Puccini's ensemble-driven second act even when the rest of Joël/Barlow's post-prandial diners looked ready to doze off.
La rondine shares a number of superficial plot shapes with La bohème, not least an emotionally uncomplicated secondary romance that acts as a counterweight to the main pairing. Here, Sabina Puértolas' richly-sung Lisette - Magda's comically liberated maid - would have benefited from a more sharply characterised partner than the foursquare Montvidas. Other parts, such as they are, were well taken by a company that included five members of the Royal Opera's excellent Jette Parker Young Artists Programme.
A touch more urgency from the pit might have helped jolly things along, but Marco Armiliato's relaxed account of the glowing, operetta-flavoured score showed little concern for the inherent drama. In an evening that smacked less of fin-de-siècle than fin de saison, this is one swallow that didn't quite make a summer.