Yes, Royal Opera House, London

The starting and finishing point for Errollyn Wallen and Bonnie Greer's chamber opera Yes is Greer's 2009 appearance on BBC's Question Time alongside the British National Party's Nick Griffin.

Entering the Linbury auditorium – opened up on this occasion to an audience on opposing sides of the action, as it were – the floor of the acting area is spattered with words reflecting the firestorm of publicity and debate which enveloped this now notorious event. But where is the debate in Greer's self-reverential libretto? Why does she suppose that by simply stating the obvious, that Britain is a nation of immigrants, and then asking "why", she has the basis for a piece cast in that most dramatic of art forms: opera? We know where Yes begins and ends – it's the void in between that is troublesome.

The issue of national identity and the evolution of multicultural Britain is, of course, one that needs to be restated and reiterated to those who would deny it and it is that – the history of this sceptred isle – that is the grouting for Greer and Wallen's piece. The inferred irony of a Muslim woman delivering an era-by-era account of our heritage set to a succession of musical parodies might be amusing if it weren't so patronising. For the really dumb among us, the names of our descendents flash up on the screen: Celt, Roman, Saxon, Norman, Dane, Viking, Huguenot, and so on. We have evolved from invaders and refugees; at heart we are a nation of immigrants; we get it. But is that it? Yes. Well, at least the title rings true.

It doesn't help, of course, that Greer is unavoidably the central character in all of this, sitting at her desk marinating in quasi-poetic thoughts ("My life is solitary"), pondering the BBC's invitation ("I said yes"), recalling her mother's advice always to "be herself". The truisms just keep coming. And the stereotypes. And the clichés. Director John Lloyd Davies keeps them coming: strobe, slo-mo, shadow play, even an animatronic cat. And amidst all the musical allusions there are only fleeting glimmers of Errollyn Wallen's undeniable talent.

"Who's listening, no one hears us", reiterates the chorus against Wallen's jazzy ostinati. One wanted to respond: when you've something to say, we'll listen. Could an hour really be so long?

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