Un ballo in maschera, Royal Opera House, London <br></br> Philharmonia Orchestra/ Mackerras, Royal Festival Hall, London

Welcome to Operaland - a Bostonian suburb of Stockholm (in Spain)

Time was when Un ballo in maschera was an American opera. Then Verdi's Boston-based blockbuster of adultery and assassination was restored to its original Stockholm setting. Opera being opera, location and periodicity rarely get in the way of a good plot. Adultery is still adultery, regardless of whether the resultant homicide is a regicide. Hence Calixto Bieito's 2002 English National Opera staging turned 18th-century Sweden into 20th-century Spain to no ill effect.

Now Mario Martone's lavish Covent Garden production has brought the Boston version of Un ballo back to London. Full circle? Not quite. For this is not the 18th-century Boston setting grudgingly approved by Verdi's censors but the 19th-century Boston of the Abolition Movement. Ah ha, I hear you say, it's a political production! No. Give or take a few periwigged slaves, politics are strangely absent from this drama. Furthermore, Martone's Boston isn't really Boston at all. It's Opera World: that timeless, placeless, sexless land of big voices, big emotions and big dresses.

Given his background in experimental theatre and film, Martone's house debut is surprisingly conservative. His cinematic CV is evident in Sergio Tramonti's opulent set designs: Act I, scene 2 is merrily lifted from Gangs of New York, while Act III's mirrored masked ball owes its exquisite colouration to The Age of Innocence. But whether Martone's hommage to Martin Scorsese will matter to an audience intoxicated by A-list casting is a moot point.

Taken separately, which is very much how they are given, Karita Mattila's Amelia, Marcelo Alvarez's Riccardo and Thomas Hampson's Renato are glorious. Though Mattila's expression of anguished ecstasy verges on self-parody, there is a compelling candour to her singing. I remain unconvinced that hers is a Verdian voice - too Nordic, too oxygenated, too heroic - but she moves it magnificently. And if in Morrò, ma prima in grazia she appears to be more interested in persuading her audience that she is desperate to see her son again before she dies than she is in persuading her husband, so be it. With Mattila emoting for two, Hampson is free to do what he does best: the self-contained smoulder.

Renato is a curiously underwritten role. By comparison with Otello, Verdi dropped the ball on Renato's compromised cultural identity. But Hampson works hard to make his silences matter as much as his singing and gives a subtly nuanced portrayal of the Creole cuckold. Camilla Tilling's pert, bright, boyish Oscar would grace any production. Elisabetta Fiorillo's lurid Ulrica would not, though she does have my favourite line in the opera. ("I must commune with Satan!") Which, of the major roles, leaves only Alvarez. Martone has obviously put in the hours with his leading man, for surprise, regret, desire and anger make brief cameo appearances on Alvarez's placid face. Sadly, they all appear a beat too late, like a frown on a Botoxed forehead, and Alvarez and Mattila are as ill-matched a couple as Streep and Stallone. Despite this, his Riccardo is more convincing than his Duke or his Werther, and his singing more lithe and expressive than I've heard hitherto.

Fresh from Die Walküre, Antonio Pappano and the Orchestra of the Royal Opera House unpick Verdi's score with due delicacy. The textures are transparent, the variations of scoring succulently highlighted, the vocal ensembles well-balanced, the smaller roles sensitively accompanied. Though over-reliant on his audience's willingness to suspend an extraordinary level of disbelief while watching Mattila and Alvarez pretend to be lovers, Martone's Un ballo in maschera is an entertaining exercise in the grand tradition of polyglot opera.

Having enthusiastically recommended the final concert in Sir Charles Mackerras's Brahms Cycle with the Philharmonia Orchestra - and implied that the performance I reviewed was the penultimate in the series, which it wasn't - I felt honour bound to attend it. OK, I lie. Honour had nothing to do with it. But who's going to turn down the chance to hear Mackerras conduct Brahms again?

Unlike the Serenade No. 2 and Symphony No. 3 of last month, Sunday's programme, which framed Truls Mork's searching performance of the Dvorak Cello Concerto with Brahms's Tragic Overture and Second Symphony, saw the full complement of players onstage throughout. Consequently, the connection between conductor and orchestra was absolute and Mackerras's fluid, Steinbachian tempi and daring dynamics were unanimously observed. The Tragic Overture was radiant and riveting. The Cello Concerto deeply affecting. The Second Symphony as enthralling and elating as it was the first time I heard it, more than 20 years ago, and ravishingly played by the woodwind and lower strings. As a reviewer, one spends a great deal of time wrestling with music that deals with alienation, grief and anguish. What pleasure to hear something so profoundly affirmative.

a.picard@independent.co.uk

'Un ballo in maschera': Royal Opera House, London WC2 (020 7304 4000), to 30 April