Mitridate, Re Di Ponto, Royal Opera House, London

Not that opera seria has much to do with real life, of course. But Mozart was well-versed in the ways of the key emotions - love, lust, anger, rage, and revenge - and even at 14 he knew exactly how to address them in vocal terms. This is a testing night for overwrought coloratura techniques and it got off to a sizzling start here when the young Polish-born soprano, Aleksandra Kurzak - as Aspasia, Mitridate's aforementioned betrothed - gave vent to her anxieties in a near-perfect display of rhythmic, evenly-produced, stratosphere-reaching coloratura singing (the Queen of the Night in embryo). Not an aspirate to be heard anywhere. What a way to launch your Royal Opera debut.

Like most opera seria of the 1700's, self-contained solo turns are the thing, elaborating on emotions opened up in the sung recitatives. Graham Vick's effective 1991 production gives them plenty of room. His spare, stylised, Kabuki- influenced staging - decked out in the vivid primary colours of Paul Brown's designs - melds Baroque and Japanese techniques and gives them a contemporary kick.

When Sifare - Mitridate's younger son (the outstanding Sally Matthews) - resolves to leave Aspasia rather than suffer the pain of unfulfilled longing, the ensuing aria with obbligato horn (where would Mozart have been here without Handel?) is already up there with the composer's mature (really mature) work. Matthews' vibrant singing, so bright and true above the stave, is developing fast. The sweet sorrow of this aria was the more affecting for seeming to demand a response from its recipient. But she, of course, remains silent, speechless.

Therein lies the genius of Mozart. He gives us just one duet in the entire evening and that at the absolutely key moment where Sifare and Aspasia resolve to end their lives together. Suddenly, the two voices unite, the emergence of vocal harmony for the first time lending a dazzling singularity of purpose.

The singing was of uniformly good, often excellent quality throughout the long evening. Susan Gritton (Ismene) is another rising British star whose shining top has a touch of ecstasy about it. Bel canto tenor specialist Bruce Ford (Mitridate) negotiated the treacherous intervals of his entrance aria with admirable elegance and control.

The consistently high (and low) tessitura never once fazed him.

Then there was the one really big star of the evening - the countertenor David Daniels (Farnace, Mitridate's elder son).

This is a voice of rare natural beauty and phenomenal range. However, I wouldn't say he was heard at anything like his best here. The audience disagreed - which probably says more about his marketing than his performance. Also disappointing was Richard Hickox's plodding, generalised conducting with its cursory nod to the vibratoless period style. But by the time the opera's one brief ensemble had wrapped things up we all left happily humming the singing.

To 17 July (020-7304 4000)