Candide, English National Opera, London<br />The Rake's Progress, Garsington Opera, Oxford<br/>Rusalka, Grange Park Opera, Hampshire

Stylish yet sanctimonious, Robert Carsen's lavish Théâtre du Châtelet adaptation of Candide documents the dismal history of the kingdom of WestFailure. You may not have heard of this place, but you will certainly recognise it. It's a world of sports cars and space rockets, cruise-liners and kitchen appliances, baby-boomers and bunny-girls, small-town evangelists and swindling oil-men, avaricious producers and ambitious starlets. It's a world of confidence, luxury, greed and power. And it's a world of poverty, pollution and war.

Hard as it is to assess what might have happened had John F Kennedy not been assassinated, it is harder still to imagine the long-term effects of an America governed on a mandate of compulsory cocktails and cute one-liners. Neither Leonard Bernstein nor Lillian Hellman was noted for their interest in green issues, yet Carsen appears to think that a United States of Algonquin would be "the best of all possible worlds".

Faulty from the moment of its 1956 premiere, Candide is not improved by this vacuous, good-looking show. Though songs like "What a day for an auto-da-fé!" (written in response to Senator Joseph McCarthy's witch-hunt) still raise a grin, and Michael Levine's set designs dazzle, the dialogue is weak, the music thin.

Where Voltaire satirised uncritical thinking, Carsen and his co-writer Ian Burton satirise only those values they do not share, illustrating the final chorus with footage of melting ice-caps. Does anyone need reminding that global warming is a bad thing?

The production is at its sharpest when it sticks to the 1950s, most particularly in Rob Ashford's Stanley Donen-inspired fantasy ballets, and at its most gauche when it presents Messrs Blair, Bush, Berlusconi, Chirac and Putin in their bathing suits, afloat on a oil-slicked sea, as the Five Deposed Kings. Easy targets and, in most cases, yesterday's men.

Problematic too is the amplification. In the title role, Toby Spence's attractive, boyish tenor is overwhelmed by a raucous orchestra and an on-off American twang. As Cunégonde, Anna Christy's coloratura is compressed into a mosquito whine, while Beverley Klein's Old Lady sounds like an apoplectic chicken. More successful are Mark Stone (Maximilian), Mairéad Buicke (Paquette) and the wonderful Alex Jennings, whose Voltaire/ Pangloss holds it all together.

For a more rigorous examination of virtue scorned, you should head to the countryside, where Olivia Fuchs's stylish production of The Rake's Progress and Antony McDonald's near-perfect Rusalka can be seen. Smartly designed and lit by Niki Turner and Bruno Poet, Fuchs's Rake takes inspiration from surrealist art and 1980s pop culture. The whores and roaring boys are post-punk teens with sullen mouths, asymmetrical haircuts and ripped fishnets, Mother Goose (Phyllis Cannan) is a bosomy Zandra Rhodes-Vivienne Westwood hybrid, while the three retainers who silently serve Nick Shadow (Christopher Purves) sport ashen faces and Magritte bowler hats.

The movement direction (Clare Whistler) is excellent but, with the exception of Purves's insinuating, sociopathic Shadow, the central roles lack definition. As poor, shuttle-headed Tom, Robert Murray sings awkwardly, his chest, middle and head registers respectively coarse, curdled and constricted. Sinéad Campbell's touching Anne, styled in pashmina and riding boots as a third Middleton sister, was too light of voice to combat the wind and the rain that intruded on stage and pit during the second performance.

Under Martin André, some orchestral detail was also lost, though, given the soggy quality of the bassoons, that might have been a good thing.

Let's hope Garsington Opera offers better shelter to its performers when the company relocates in 2010.

Played out in a sinister woodcut, with a pale, cold moon and leafless, grey-green trees, McDonald's Rusalka is virtually flawless: dream-like, violent, mournful, amoral, funny, immaculately lit and choreographed, and very disturbing. Odd blips from a drowsy-sounding trumpet section aside, it is musically magnificent too, thanks to Stephen Barlow's understated reading of Dvorák's score.

In Anne-Sophie Duprels, last season's Cio-Cio San for Opera North, Grange Park have a heartbreaking heroine: feisty, vulnerable, compelling to watch in her mute wretchedness. Though Jeffrey Lloyd-Roberts strains at some of the Prince's heroic phrases, the supporting cast is one any company would be glad to have, with Anne-Marie Owens an enigmatic, surprisingly sexy Jezibaba, Janis Kelly a predatory Foreign Princess, Clive Bayley a stern Merman, and three outstanding nymphs (Joanne Thome, Anna Grevelius and Karina Lucas).

Under ordinary circumstances, I think you have to be one of Grange Park's sponsors to enjoy its rarefied Petit Trianon atmosphere. For this extraordinary Rusalka, I would urge any opera-lover to borrow a bow-tie, remortgage, pack a sandwich and go.

'Candide' (0871 911 0200) to 12 July; 'The Rake's Progress' (01865 361636) to 6 July; 'Rusalka' (01962 737366) to 9 July