Brought to London as one of the opening attractions of Tête à Tête's Opera Festival, The Weatherman is Opera North's contribution to this year's Darwin bicentenary celebrations. With music by Paul Clark and words by John Binias, it sets out to explore the relationship between the scientist and the profoundly conservative Robert FitzRoy, captain of HMS Beagle and pioneering metereologist, who killed himself a few years after the publication of The Origin of Species.

The story of their friendship and subsequent estrangement is told in a breathless narrative, delivered by Sarah Belcher, while FitzRoy's thoughts are voiced by a baritone, Robert Poulton. It is all underpinned by a relentlessly anonymous string quartet. The clutter of sung and spoken text is hard to follow, the chronology is confused and the whole piece loses its way towards the end, when it lapses into a mawkish and half-baked celebration of the wonders of evolution.

Like so much of what the Tête à Tête programme promises, The Weatherman hardly qualifies as music theatre, let alone opera. The soi disant Opera Festival may claim to be broadening the audience for the art form through all-inclusive programming, but it is doing so by opting for quantity rather that quality and abandoning any kind of sensible definition of what opera is. Hence the late-night inclusion of The Emergency Recital, by Richard Thomas, composer of Jerry Springer: The Opera and librettist for Mark-Anthony Turnage's forthcoming Covent Garden commission.

With singers Loré Lixenberg and Adey Grummet it was a pleasant and sometimes hilarious hour of Thomas's songs and musical one-liners on a whole range of vaguely risque topics, but which had absolutely nothing to do with opera. Tête à Tête would doubtless say, though, that it's all about breaking down barriers.

The Opera Festival continues until 16 August. Box office: 020-8237 1111.