This has long been a standout date in the Royal Opera's diary; we were not disappointed. True, most interest was focussed on Rolando Villazón, and not just because he took the title role. He did well on this first night; well-acted and well characterised, his golden sound and easy phrasing in place as early as his first appearance - and Don Carlo is the first personality we meet, here in a snow-clad forest. True, Villazón's voice did prove to be a little gruff at times and his pitching wasn't always exact, and he was not quite as secure as Simon Keenlyside when Don Carlo and Rodrigo swear an oath of allegiance. If anyone was flat or slightly behind it was Villazón - ironic then that immediately after this duet he is left alone on the stage and Rodrigo has departed. The audience gave Villazón a long ovation but the more-deserving singer had departed! But, then, applauding in mid-act does not do the long line of an opera any favours.

And Verdi's operas are thought-through; Don Carlo may be an editorial minefield, but it deserves to be heard uninterrupted. Antonio Pappano links Acts I and II, and Acts IV and V, the two intervals framing Act III. It's a long evening by the clock (something like four and a half hours, including intervals), and you will now know that Pappano conducts the five-act Italian version (1886 Modena) - there are quite a few editions of the opera (in four acts, and five, in Italian and in French). It is however a short evening, dramatically riveting and notable for a strong cast working well together. It isn't just about Villazón (he portrays an suave, gallant and impassioned Don Carlo - well befriended by Keenlyside's Rodrigo) and bonded by Pappano's exacting and dramatic conducting that is rewarded by some superb brass playing, which, indefinably, has the right sound and rhythmic guile that is echt-Verdi. The clarinet and cello principals were stars, too. The strings produced some wonderfully moonlit timbres.

The first act is the one that can be dropped; but it was needed here - but only in retrospect, for the unfolding tragedy really makes its mark when one remembers the almost-idyllic circumstances of the first and love-at-first-sight meeting between Don Carlo and Elisabetta. Marina Poplavskaya plays her, and is regal of stature and of tone. Don Carlo's father, Philip II, is taken by Ferruccio Furlanetto - very impressively. He rather than Don Carlo marries Elisabetta and is a troubled figure, such emotions seeping out, not least when discussing grave problems with the Grand Inquisitor such as the proposed execution of Don Carlo (his own son, that is). Eric Halfvarson gives the all-powerful Inquisitor - despite him being blind and requiring the company of two helpers - significant presence.

Nicholas Hytner directs and Bob Crowley provides the designs; it's a good team - there is little that doesn't seem to belong to the drama while the scene-setting (whether garden, town or cathedral) have both a storybook look and also a potent sense of presence and significance; Valladolid Cathedral is a striking scene, with heretics and golden spectacle - Boris Godunov is not far away. This is an epic and complex opera - these qualities are retained here but the narrative (both historical and revealing about human emotions) is an absorbing one and the dimensions of the work never seem overlong or verbose; even those (few) moments that seem too much a diversion (albeit pleasing ones) make their points eventually when a moment of drama is the inevitable follow-through.

There is much to admire in the pit - from subtlety to power - and the singers have come together to form an ensemble that serves the story. A curiosity is that the singers' dynamic range changes dramatically if they move very close to the front of the stage in a manner that is more to do with the acoustic rather than considered changes of volume. A small point this; and I also wondered about Sonia Ganassi as Princess Eboli; but not when she had 'grown' into her part and really established herself and her character.

All in all, this is a Don Carlo that reminds as to Verdi's great achievement and that The Royal Opera has assembled a stellar cast and, in Tony Pappano, has a conductor really appreciative of Verdi's genius for characterisation and dramatic impulse. Performances are until 3 July (and should you be in London, or Liverpool, on the evening of the final performance, this is screened to Trafalgar Square, Canary Wharf, and Clayton Square (Liverpool), both live and free, and BBC Radio 3 broadcasts the opera on 28 June.

Don Carlo is a relative rarity - it has been absent from Covent Garden for 20 years (although the French-language version was performed in 1996, under Bernard Haitink, although he went on to record the Italian five-act version), and its 'rehabilitation' is found here to be well-timed and thoroughly impressive in both performance and staging.