Cosi Fan Tutte, Glyndebourne, Sussex (01273 813813) 5pm

Dust down your luxury hampers, Glyndebourne is upon us once again. Kicking off the season is Graham Vick's production of Cosi Fan Tutte, the first in the cycle of Mozart / Da Ponte operas (Le nozze di Figaro and Don Giovanni) that he will stage in the run up to the millennium. Cosi Fan Tutte was actually written last, in 1790, and has taken the longest to secure its reputation. Victorian England deemed this geometric tale - in which two officers attempt to test their lovers' fidelity by wooing them in disguise - too lightweight. But its revelations about the malleability of human desire and identity have struck a deeper chord this century. Glyndebourne rescued Cosi's reputation in its first season in 1935. Its last production was Trevor Nunn's glitzy cruise-ship romp, much revived since 1991. Now Vick takes things to the opposite extreme, pointing up the improvisatory nature of the plot by staging the action as a rehearsal. Not everyone does that.