MUSIC / Egyptian knight: Meredith Oakes on mixed performances in Haydn's L'Incontro Improvviso at Garsington

The title, 'The Unexpected Encounter', tells you at once that it's one of those operas where nothing's unexpected, least of all the encounter. The plot and the poetry make Blackadder look suave, but the score is elaborate, rich in melodies and stocked with those Haydn devices that seem to pre-date more famous instances in the works of later masters.

Haydn wrote it in 1775, on a recycled libretto. It tells of Prince Ali who, seeking his beloved in Cairo where the Sultan of Egypt is keeping her prisoner, is summoned to a mystery woman's house. Two handmaidens make advances to the Prince but he rejects them: then the mystery woman appears - the Prince's beloved who has been testing his fidelity. The lovers escape and are captured, but the Sultan forgives them and they marry.

Stephen Medcalf's Garsington production skips the existential angst and goes for the harem trousers. In Isabella Bywater he has a designer very well attuned to the joky fantasies and hand-me- downs of country-house dressing- up, and very good at making singers look sexy.

But did they sound sexy? Tenor Paul Nilon, wearing a paunch in the clowning gluttonous role of the Prince's servant Osmin, took all the honours: a bright, flexible, caressing voice able to be passionate in the midst of stylish play-acting. Thomas Randle started in trouble as the Prince, the pitches in his recitative were impressionistic and the vocal texture in his first aria stressed. He warmed up, but his best moments involved careful crooning, not free mastery.

Soprano Lynne Davies had it all as the Princess's confidante Balkis: great vocal presence, clean-sounding, a bit young, but with heart and depth to the tone; a grounded, eloquent interpretation. The virtuoso role of Princess Rezia presented Eirian Davies with no overwhelming difficulties, but her singing lacked the necessary extra layer of voluptuous ease. Similarly Roger Bryson, as Calandro, the mendacious mendicant monk was capable, needing either to relax or to take it a step further and become truly manic.

The designs left the Garsington stone loggia visible at the back, while giant sand-coloured antique maps were draped and strewn across the stage, alongside wooden scaffolding, and a pair of carved deal staircases on wheels. The overture was spent, Opera Factory style, furnishing and dressing. The feeling was one of smart improvisation. Medcalf used the two moveable staircases to pose the singers Broadway- style, or to poise a torch-waving soprano perilously at the top.

The orchestral playing at Garsington, quickly organised in the open air, always has something of the quality of a thrown cat landing on its feet. The cat landed with dexterity and some grace on Saturday, though the inner strings were slightly woozy. Wasfi Kani (the company's associate director) conducted.

Further performances of 'L'Incontro Improvviso' at Garsington on 29 June, 3 and 8 July (Booking: 0865-361636)