Raymond Gubbay is on to a winner with his Albert Hall arena operas, of which David Freeman's 1998 staging of Madam Butterfly, now on its second revival, is one of the best. Yet Butterfly, if staged properly, should be anything but safe. This is an opera about all kinds of betrayal, about crushed hopes, and - topically enough - about the fatal results of American impatience with another culture. The tenor, a hero in most Italian opera, is here a cowardly bigamist with a penchant for underage girls. Don't let the fact that some of it sounds pretty fool you. This is sordid stuff.

Still, David Rogers's designs are as beautiful as you could ask for, at least in the first act, before the Japanese water garden surrounding Butterfly's house is drained to reveal something more lonely and austere. And Freeman's production is as effective as ever. With the exception of Butterfly's heartbreaking vigil during the interlude between Acts 2 and 3, it's never static, yet there's always a feeling of focus.

There is, however, a serious problem: not nearly enough of the words come across. As the company is performing in English, in Amanda Holden's flowing translation, that's a shame.

Opera in the round, in a venue as cavernous as this, needs a little acoustic help, but the sound system seems more of an intrusion than it has been previously. The Royal Philhamornic can sound blurry, and conductor Peter Robinson finds it hard to balance his players with the singers, sometimes overpowering them.

Moreover, while Ai-Lan Zhu sings beautifully in the title role, her diction, and that of Carlo Scibelli's Pinkerton, is less than crystal clear. Lines of his that should raise a smile (or a grimace) go unnoticed. Phillip Joll's Sharpless and Aled Hall's Goro offer some consolation, and Ai-Lan Zhu's portrayal of Butterfly's naivety and her awakening is convincing. It's a moving experience - but don't expect the involvement that would come from hearing every word.

· Until March 9. Box office: 020-7838 3100.