You have to hand it to Andrew Lloyd Webber: few contemporary theatre composers write with such an expansive or eclectic musical voice. After the operatic-like intensity of The Woman in White, the return of Whistle Down the Wind to the West End (as a temporary filler at the Palace Theatre before the autumn arrival of Monty Python's Spamalot from Broadway) finds him writing in his most explicitly pop rock idiom since Jesus Christ Superstar.

While form does indeed match content here for a tale - based on the Mary Hayley Bell story originally set in Sussex, subsequently changed to Lancashire for the 1961 film version, and here relocated to one of kids growing up in an American South of the 1950s that was itself waking up to the sounds of rock 'n' roll - too much of it, however, is phoney and hokey.

Characters may screech of "tyre tracks and broken hearts", but the main sound that’s heard is of tired tracks and broken lyrics. Songs for the vast child choir army - there are over 30 of the Carmel Thomas Youth Singers on stage here - like “When Children Rule the World”, could come straight out of a Coca-Cola ad in sentiment as well as melody, while the soupy pop ballad of the title song is endlessly reprised. But no matter how you resist, a song like “No Matter What” embeds itself in the memory as insistently as “Memory” from Cats. No wonder it has proved to be one of Lloyd Webber's biggest break-out pop hits since then. With other, less plaintive attempts to be alternately raunchy (“A Kiss “s a Terrible Thing to Waste” with its loud orchestral riffs that dissolve into ballad-mode) and dramatic (“The Nature of the Beast” could be a steal from Les Miserables), the show is full of jarring shifts of emotional register that try to have it, by turns, simple and direct versus edgy and throbbing.

But while the original 1998 London production of Whistle Down the Wind (which ran for two-and-a-half years at the Aldwych) saddled the show with a clumsy, frequently malfunctioning design and a pretentious production, Bill Kenwright's touring revival is palpably both far simpler and more sincere. The approach pays some dividends to return the show to its original impulse of updating a beloved story of the wide-eyed innocence and naivety of children who think they've discovered Jesus Christ in their barn to a believable era.

Kenwright's strongly sung production, on Paul Farnsworth's set that puts an imposing wooden barn on stage, gives it full dramatic weight, with Tim Rogers bringing an ardent tenor of desperation to the convict and Claire Marlowe's Swallow combining vulnerability and an awakening knowingness.

- Mark Shenton