Subtlety and open-air theatre are not natural allies, but there is a complexity about Timothy Sheader's production - a genuine understanding of the play's gender politics and its erotic undercurrent - that works very nicely here. With a hot-blooded, Spanish colony setting working in its favour, up until the interval this promises to be an exceptional Twelfth Night; if the promise ebbs away after the break it is because the production fails to sustain its energy, and some of the unevenness of the casting becomes an irritant.
It is still a largely delightful evening and one with some interesting insights: it is clear that despite the final pairing off of Viola and Orsino and Olivia and Sebastian, there is always going to be a third person in each of these two couplings. Sirine Saba's Olivia seems as intrigued as she is unsettled to discover that the object of her affection is female.
Saba's cigar-smoking Olivia is a pleasure: comic, giddy and vulnerable in love. She is well matched by Mariah Gale's wan-faced Viola, who sings every line straight from her shipwrecked heart. There is a really terrific Feste, too, from Simon Day, a strange, watchful shaman-type figure sporting a goat skull on his head, whose mixture of wit and tenderness provides the calm centre in this whirligig world of emotions.
There are so many wonderful touches - Viola's attempt to walk straight back into the sea when she discovers her brother is dead; the transference of desperate griefs into desperate loves; the sexually charged, puppyish wrestling of Viola and Orsino - that you suspect this side of the play interests Sheader rather more than the comic. The comedy pretty much looks after itself. Anyone requiring further persuasion to spend a balmy evening in Regent's Park, should know there is a parrot. You can't go wrong with a parrot.
· Until September 1. Box office: 08700 601811.
