The story of Swan Lake is woven around two girls, Odette and Odile, who resemble each other so closely they can easily be mistaken for the other. Originally their roles were entrusted to two separate dancers, but as there is only one brief fleeting moment when they are seen simultaneously, it has long been customary for a single prima ballerina to perform both parts, differentiating them by characterisation and general style. The action takes place in Germany in the distant past. 

Act I

After a glittering musical introduction, the first scene is set in a splendid park, with a fairy-tale castle in the background. Prince Seigfried and his friends are seated, drinking, and peasants enter to congratulate him on his coming of age; meanwhile, his tutor Wolfgang encourages them to dance for the young Prince's entertainment. 

A messanger presages the arrival of the young Prince's Mother. She follows to pronounce that her son should now marry, choosing a bride from the young women to be presented to him at a ball the following evening. She leaves and the rustic dancing resumes until darkness suddenly falls and a flock of swans appear. The Prince has an idea of shooting one of the noble birds and, armed with a crossbow, sets off with his friends and heads to where the swans are heading. 

Act II

By the banks of a lake by moonlight, a flight of swans glide past, led by their own Queen. The Prince's friends are eager for the chase, but he begs them to leave him, and whilst he is alone the Swan Queen comes to him in the human form of Odette and tells her story.

She is under the spell of an evil magician, Von Rothbart, and reveals that by day she and her friends are turned into swans. Also persecuted by her stepmother, that subjection will only end when she marries; until then she has only her crown to protect her.

The whole swan group arrives and they reproach the Prince for attempting to deprive them of their beloved leader. Odette intercedes and the Prince discards his crossbow. He and Odette dance, professing their love. The entire flock joins in; and the act ends as an owl (the wicked stepmother) flaps heavily above. 

Act III

It is the following evening and in a luxurious hall in the Prince's castle preparations are underway for the feast. Wolfgang orders the servants around; guests start to materialise; and finally, the Princess-Mother and her entourage. A sequence of turns commences until the Princess asks her son which of the women he favours. 'None', he replies to her annoyance. 

At a sudden fanfare Baron Rothbart enters with his daughter Odile, whose resemblance to Odette strikes the Prince. Odile herself dances enticingly, followed by an elaborate sequence of national dances by the company. The Princess-Mother is pleased to see that Odile has caught her son's favour. The young couple themselves conjoin together and the Princess-Mother and Rothbart advance to centre-stage to announce a betrothal. 

With that, the scene ominously darkens, an agitated version of the principal swan theme is heard; a window flies open noisily and through it can be seen a white swan replete with crown. Horrified, the Prince pushes Odile away and rushes out amid general confusion. 

Act IV

The girls, including Odette, gather around the lake. Odette is heartbroken. Prince Siegfried finds them consoling each other. He explains to Odette the trickery of Von Rothbart and she grants him her forgiveness. It isn’t long before Von Rothbart appears and tells the prince that he must honour his word and marry his daughter or both he and Odette will die. Prince Siegfried refuses. A fight follows, Odette and Siegfried die in each other’s arms. Von Rothbart’s evil spell is broken by the power of Odette and Siegfried’s love for each other and Von Rothbart is destroyed by the swans, who are released from their enslavement. 

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