Opera: Elektra Royal Opera House, London

A curse weighs heavy on the House of Atreus. Blood will be avenged with blood. There will be much gnashing of teeth and several top Cs. Greek mythology the Strauss way. Elektra. And as if to nurse vocal resources, Covent Garden is fielding two separate sets of principals for its current revival. Two casts, two households, staying, slaying, decaying together. But one conductor: Christian Thielemann. Thielemann is a dynamic young German with old attitudes. A new breed propagating old musical values. He conducts this wild and wonderful score like it's going out of fashion. In a word, sensationally. It's a reading so overripe that it's beginning to smell. The colour and cast of it are thoroughly modern, the sonic madness scrutinised and projected with ruthless clarity. The opening declamation - a body-blow that seems to surprise even Strauss - dissolves into a woodwind chord so black and hollow, it's like looking into the eyes of a skull. There follows one long hallucination - ugly and beautiful. But the bigness of gesture, the lushness of Thielemann's rubatos (post-radical chic) belong to another era entirely. Put it all together, and it's like Boulez has been crossed with Karajan. Orchestrally, then, thrills aplenty.

Gotz Friedrich's "tunnel vision" of the opera is more set than psychology. The central metaphor (designer Hans Schavernoch) is a sewer or, if you prefer, a disused section of "the misery line". We are inside Elektra's head, and it's not a pretty sight. Self-loathing rarely is. The trouble is that Friedrich (or rather the revival director David Massarella) allows for rather too much operatic posturing. The emotional and the physical are too often separate events. As Grand Guignol, it's fine. Klytemnestra is still very much the wicked fairy keeping up appearances (a caped Cruella on crutches), while Chrysothemis - a kind of wannabe Jean Harlow, all sequins and white mink stole - is the debutante-in-waiting, a pathetic remnant of the high-life, doomed to remain unloved and childless.

Karita Mattila swept into this role in full realisation of its desperation. It's a big sing for her. She was passionate, unstinting. She always is. There were some huge notes, bigger and better notes than we heard from the somewhat squally Nadine Secunde in the second cast. But I sincerely hope that this is the limit of her living dangerously.

Klytemnestra, the mother of unsuitable mothers, is a great role for Felicity Palmer. When she speaks of "slaughter, slaughter", she is relishing the sound of the word as surely as the deed itself. Every word is formed here with the taste of bile in her mouth. Jane Henschel sings it better, her sepulchral lower register a real boon when it comes to freezing the blood. But I'm not awarding points. Suffice it to say that Thielemann's astonishing nose for atmosphere turned the nightmare monologue into... well, a nightmare.

It's one of the great paradoxes in opera that the dramatic soprano who is ready, really ready, to take on the title role is, by definition, at the "lived-in" stage vocally. It's one thing having the notes, the strength, the stamina to get through the part, quite another to convey the damage, the terrible cost of hatred. Deborah Polaski and Hildegard Behrens are both experienced hands, wearing the part like the skin they long to shed. The wildness, the recklessness is inherent. Polaski is in better vocal health than Behrens (notwithstanding the latter's untimely throat infection), but Behrens, oddly enough, has more reach at the top. In fortissimo. It's when she attempts to sing quietly that you hear the damage. A threadbare legato. But she's still spitting like a cat from the chest voice (the root cause of her vocal demise): a weird kind of sprechgesang, very visceral, often very exciting. And she is still a sad, grave presence on stage - as witness the powerfully static "recognition scene" (Robert Hale and Alan Held, both suitably gaunt in voice and stature as Orestes). But the piece rules - and what a piece.

Further perfs tomorrow, Saturday, 27 and 31 May. Booking: 0171-304 4000 Edward Seckerson