The best opera productions are always the ones in the mind's eye. Nowhere is this more true than in the case of Pelléas et Mélisande, Debussy's symbolist opera from the turn of the past century - a work of shadowy emotions and elusive characters which leaves everything that really matters to the imagination.

Productions of this tricky opera have come and gone fleetingly at the Royal Opera in the past 50 years. This latest is a co-production with the Salzburg Easter Festival, where it originated last year. The festival's artistic director is conductor Simon Rattle and, in wanting to lure him back to Covent Garden, the Royal Opera was presumably obliged to take Stanislas Nordey's mind-numbingly vacant production as well. That seems to be the science of co-productions - if you want the star, you get the black hole as part of the package.