Whale tale makes you cry

Whether you see Moby Dick as a critique of Calvinism, a hymn to the struggles of 19th century American democracy, an exploration of the intangibility of the self, or a rollicking yarn about cannibalistic bedfellows, obsession, and of course, whales - among other matters - prepare to be bemused.

This profoundly irritating musical response, composed by Rinde Eckert, is simultaneously as clumsy in structure as a beached whale and as evanescent in impact as a retiring jellyfish, leaving certain audience members uncertain whether to abandon ship or look for hope among the clunking conceptual wreckage.

It sounds, initially, like an idea with not so much wings as fins: a composer who is gradually losing his memory (to the point, we learn, where he will forget to breathe) is simultaneously trying to create an opera based on Herman Melville's glorious mess of a novel.

A perfect case-study for Oliver Sacks, one might think, except rather than The Man Who Mistook His Wife For A Hat, this is The Man Who Mistook His Muse For A Fact, since this composer has an imaginary female friend whom he allows to guide him and nurture his brain cells towards a final lunge for musical greatness.

Moments to be salvaged from this ocean of self-indulgence are few - though there is promise in the drily comedic start, where a series of colour-coded tape recorders are identified for functions ranging from reminding the composer of his name (Nathan) to recording his philosophical reflections.

On the set, rows of light bulbs hanging from long cables, and a grand piano bound in rope and post-it notes initially create the feeling that one has stumbled into Tate Modern, yet despite vivid blue, green, and at one point, red lighting, it is difficult to feel that one ever progresses from a modern art gallery to the ocean.

Eckert is respected as an intellectual and Renaissance man, and, frustratingly, it is possible to glimpse evidence of this in flickers of humour, the agile compositional flourishes and in such questions as "What if the mind is a digital code that can be encrypted in music?" However, a worrying predilection for over-literal metaphor, an unamusing Muse and untantalisingly elliptical novel extracts eventually drown both sympathy and the will to live.

Until 14 June. Box office: 0845 120 7557.