Charles Mackerras first conducted Figaro in 1951. His 1965 performances at Sadler's Wells, in which he reintroduced 18th-century vocal ornamentations, sparked a performance revolution that continues to this day. Now 82, Mackerras understands Figaro better than anyone alive. On this evidence, he still conducts it better than anyone, too. From the scintillating overture, he was on top form, demanding the most attentive singing from an experienced cast who gave him their all. Perhaps the years told towards the end when the ensemble occasionally faltered, and Basilio's and Marcellina's final act arias were cut, but this was emphatically Mackerras's night.

The Royal Opera has been criticised for over-parting in important roles. No such complaints are possible here, with a cast combining the best of new and old. Ildebrando D'Arcangelo's dark baritone is an ideal Figaro voice and he looks the part. Aleksandra Kurzak's sexy and incisive Susanna matched him all the way. Barbara Frittoli is the most musical Countess among modern singers, and her fellow Italian Anna Bonitatibus sang a lovely Cherubino. Best of all was the suave-voiced Swedish baritone Peter Mattei's house debut as the Count, outstanding in his third act aria.

It is hard to think of a more strongly cast Figaro in London since the Karl Böhm performances 31 years ago, with Hermann Prey in the title role. Yes, there are some vocal blemishes and things to dislike in David McVicar's sometimes over-fussy 2006 production, here revived by Leah Hausman, but in Mackerras's hands this is simply an unmissable Mozart masterclass.

· In rep until July 12. Box office 020-7304 1200. Broadcast on Radio 3 on July 5.