Certain their fiancées could never betray them, the soldiers Ferrando and Guglielmo accept a wager from the cynical Don Alfonso. They stage a departure for war and return in disguise, each courting the other’s beloved, with the maid Despina cheerfully assisting. Dorabella gives in quickly. Fiordiligi resists and then does not. A double wedding is halted by the soldiers’ sudden reappearance, and the four are left facing what they have discovered about themselves.

The title ‘all women behave this way’, is Don Alfonso’s verdict, not Mozart’s. The opera stages an experiment in which everyone is exposed: the men who set the trap prove as fragile as the women who fall into it, and nobody ends quite where they began.

Mozart tells this largely through ensembles in addition to arias; beautiful trios, quintets and a sextet in which several people sing different truths at once, and the orchestra quietly knows more than any of them. The farewell trio ‘Soave sia il vento’ is so serene, so lightly rocked by the strings, that the joke simply dissolves inside it. Fiordiligi’s ‘Come scoglio’ declares immovable constancy in leaps so absurdly heroic that the aria mocks its own singer. Despina’s advice to her mistresses is brisk and worldly. The wind writing carries much of the tenderness, with clarinets and basset horns shadowing the voices through the opera’s most exposed moments. Mozart wrote music far too sincere for a deception, which is exactly why audiences have argued about the ending for two centuries.