Concert performances of opera have been integral to Colin Davis's work with the London Symphony Orchestra ever since he became their music director in 1995, though his latest choice, Verdi's Falstaff, is something of a new departure. In the past, Davis has tended to revisit works that have marked former high points in his career. Falstaff, however, is an opera with which we haven't associated him - until now, that is, for this is a magnificent interpretation that ranks among the finest.

Though far from humourless, the opera's dominant tone is one of sadness. Youth is seen from the vantage point of age, laughter is experienced through tears. It's ravishingly beautiful - but beneath the beauty lurks a touch of cruelty that derives from the "thieving world" of plots that try, and fail, to bring Falstaff down.

The piece's impact, however, derives as much from Michele Pertusi's performance in the title role as from Davis. His Falstaff is not so much a deluded braggart as a man whose charm and sexual powers are threatened by age and bodily decline. When he regales Alice with tales of his glamour days at the Duke of Norfolk's court, we realise that, unlike most Falstaffs, he is telling the truth. His determination to "carry on until the grave" hints at existential defiance. Tormented by the merrywives in Windsor forest, he nearly breaks into sobs as despair briefly takes over.

The rest of the cast get it absolutely right, too. Carlos Alvarez, all curly hair and Van Dyke beard, is the pomaded, preening, dangerous Ford. A hint of acid in Ana Ibarra's voice makes her Alice malicious as well as gracious. Jane Henschel is the bawdy Quickly and Maria Jose Moreno an impishly rapturous Nannetta, while Bulent Bezduz's matinee-idol Fenton is a real Romantic dreamer. Glorious, every single second of it.

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