"Thank 'eavens for leedul girls/ For leedul girls get beeger every day." The Lerner and Loewe musical Gigi is not going to win any awards for political correctness with its story of a girl being groomed for the family business of high-class prostitution. So you could argue that it's wittily defiant of the Open Air Theatre to stage a revival now. This was the first musical I was taken to see at the cinema as a toddler and no one thought it incongruous. How times have changed.
Timothy Sheader, the director, insists that "the courtesan in the belle époque is an important chapter in the liberation of women". OK, but I can't help recalling, in this context, the perverse reading of Pinter's The Homecoming that suggests it's a feminist triumph when the young woman goes on the game for her disgusting in-laws.
But audiences will roll up for this show wanting Gallic glamour, elegant frocks, evocative tunes and strenuously witty dialogue. And it mostly delivers the goods. Topol puts on a huge charm offensive without being, well, offensive, in the Maurice Chevalier role of the smarmy bon-vivant uncle. Thomas Borchert is on song in every sense as the romantic lead – he's extremely appealing as love steals up on the character and reveals chinks of vulnerability in the practised sophistication.
Lisa O'Hare is mightily winning once Gigi starts to blossom into womanhood. Before that, she seems too experienced to convince as a gamine trainee cocotte. One of the great joys of the production is the lovely, sly wit of Steven Edis's orchestration, which gets up to all kinds of clever cheek as it gives a fresh boost to such well-worn numbers as "The Night They Invented Champagne" and "I'm Glad I'm Not Young Anymore". There's humour in the design, too (by Yannis Thavoris), as pillar-box hoardings open up and unfurl to reveal classy mirrored interiors. Millicent Martin brings her personal warmth to an attractively understated portrayal of Mamita, while Linda Thorson is gloriously over-the-top as the formidable Aunt Alicia.
Gigi is a poor man's My Fair Lady, a less emotionally involving rehash of the Pygmalion myth. But it's a pleasant way of spending a summer evening in the park.
To 13 September (08448 264 242)