Siegfried, Royal Opera House, London

Act I of Warner's Siegfried is audacious, exuberant, even insolent in its execution: a loud, wet raspberry blown at the culture of Wagner as a monolith. Warner and Antonio Pappano have identified a Singspiel quality in Mime's music. The orchestral accompaniment is wry and dry as dust; the stage business a blend of screwball Yiddish comedy and - in Mime's crazed cookery demonstration - the surrealism of Lewis Carroll's pepper-addicted Duchess. Siegel, whose curtain call was one of the loudest I've heard, is the Steve Martin of opera: fearless, virtuosic, yet curiously pathetic.

Physically and vocally, Treleaven is more of a Tristan than a Siegfried: a battle-weary soldier as opposed to a boy-hero whose adventures have hitherto involved no moral crisis. Though his intonation is uneven, he sings persuasively but fails, in my opinion, to capture the most crucial aspect of his role: the "stillness of heart" that offsets Siegfried's bumptiousness. His interior world, as depicted in Stefanos Lazaridis's designs, is that of a child. Act II sees the apocalyptic shell peel upwards to reveal a grassy bed and a forest animated by whey-faced puppeteers. White deer on wheels like gargantuan children's toys symbolise his parents, while the Woodbird (Sarah Fox) spins her fluttering image in the air. A giant dragon's head leers out like a fun-fair shocker during Siegfried's slaughter of Fafner (Phillip Ens), and much fun is had with his decapitation.

As in Die Walküre, a pattern has emerged. The first act is domestic, the second dramatic, the third philosophical. As in Die Walküre, the last act is the most impactful: cleanly designed - with a dramatic extension of the abstract revolve, and a breathtaking coup de théâtre in the closing bars - and utterly focused in its development of Siegfried and Brünnhilde. I hope it is not too unchivalrous to say that Lisa Gasteen is not a singer one associates with soft sensuality. Here, lit beautifully by Wolfgang Göbbel at her awakening and singing with a warmth of tone as yet unheard in her Brünnhilde, she is radiant. The mixed emotions in her response to Siegfried, the physical passion, the fear that she teaches him by painful example, and the acknowledgement that their union is an act of rebellion that will tilt the world on its axis, have never been so eloquently argued.

Excepting Treleaven's unreliable intonation, this is a magnificently sung performance. The playing too, most especially from the woodwind, is also exceptional. Against this, changes in casting have affected the continuity of Warner's vision, and, I would hazard, Pappano's ability to meld their characters' orchestral motifs. Impressive as John Tomlinson's Wanderer/Wotan is when fulminating like an Old Testament prophet at Jane Herschel's drowsy Erda, his acting is too broad for what is otherwise a subtler style. Bryn Terfel, who will take the role when the cycle is performed in full, and whose maturation as an artist has been so fascinating to watch thus far, was sorely missed. In a similar vein, Peter Sidhom's Alberich - a vast improvement in every respect on Günter von Kannen's impersonation - makes one long to go back to the beginning and start again. Which, come to think of it, is exactly as it should be.

a.picard@independent.co.uk

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