With one opera left, Covent Garden's Ring has established itself as musically excellent and theatrically compelling. You may take issue with Keith Warner's business-laden production, or Stefanos Lazaridis's rarely poetic sets, yet the intelligence of their overview, in which the human dimension is paramount, shines through.

Siegfried is often said to be the opera that sorts out Wagner junkies from part-timers. Much of it consists of pairs of men shouting. First we see the revolting Mime, gorgeously characterised by Gerhard Siegel, bickering with the hero of the title. Downstage, a Heinkel has just crash-landed.

Grimm-inspired pantomime joins hands with sober German Expressionism. All is explained in Gary Kahn's book, The Power of the Ring, which accompanies this cycle.

Siegfried may be an oafish numbskull, but he has the most challenging role in the operatic repertoire. John Treleaven struggled when the production was new. Whatever vocal press-ups he's been doing in the interim, they're working and he wisely saved his best for his ecstatic love duet. Peter Sidhom's richly human Alberich was masterly. Phillip Ens (Fafner), Jane Henschel (Erda) and Ailish Tynan's air-borne Woodbird were first class.

Wagner conductors are made not born, and Antonio Pappano is growing into a fine one, lyrical and expressive rather than fat and beefy. John Tomlinson, in the epic Wotan-Wanderer role, first cool with fedora and pipe then pitiful as a raging Lear in fool's nightie, deserved his standing ovation.