There have been worse musicals than this, but it's hard to think of one that's duller. Written by the composer Marvin Hamlisch, lyricist Carole Bayer Sager and with a book by Neil Simon, the show, which had its premiere on Broadway in 1979, is loosely based on Bayer Sager and Hamlisch's real-life relationship. Presumably the pair thought the ups and downs of their romantic and creative partnership sufficiently fascinating to sustain an audience's interest; they were wrong.

This is a twee, utterly pointless and instantly forgettable work. Fiona Laird's revival - the first in London since the original West End production in 1980 - offers forced sitcom perkiness and uncomfortable lead performances by Connie Fisher and Alistair McGowan. McGowan is Vernon Gersch, a successful composer; Fisher, in her first stage role since The Sound of Music, is Sonia Walsk, an eccentric, hard-up lyricist with a wardrobe of second-hand theatrical costumes. The moment she turns up at Vernon's apartment, breathless, late and wearing a dress from a production of The Cherry Orchard back to front, there is, supposedly, push-pull chemistry. “She's a flake, I'm a flake. Two flakes is the beginning of a snowstorm,” Vernon wisecracks. More to the point, he's a neurotic smartarse doing wry New York Jewish shtick for all he's worth; she's an irritating kook who rarely makes a statement without presenting it, face front, to the audience. There's no contemporary American composer to touch Vernon, she gushes; well, “maybe Stephen Sondheim”.

The idiocy of the comparison is painfully underlined by the show's score, a string of pappy, poppy numbers that suit neither of the actors' voices. Fisher's style is too musical theatre for the cheesy Seventies easy-listening vibe; McGowan has a tendency to sing through his nose and to lapse into uncontrolled, over-wobbly vibrato.

The only other characters to appear are Sonia and Vernon's alter egos - three apiece - who supply backing vocals and fill out Sam Spencer-Lane's retro choreography, executed on the glossy LP record revolve of Matthew Wright's design. So there's no relief from hackneyed rom-com, and no dramatic substance to offset the bland tunes. Like an admirer with an unwelcome crush, this show wants so desperately to be liked that you can't help loathing it. It's silly, shallow and maddeningly tedious.

Box office: 020-7907 7060

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