We arrive on Alcina’s island with Ruggiero, a kidnapped knight who has been stolen from his fiancée Bradamante. On this island live Alcina and Morgana, two deadly sorceresses who are known for their seductive powers and magic.
Bradamante arrives on the island, searching for Ruggiero with his former tutor, Melisso. Dressed in armour, Bradamante impersonates her brother Ricciardo.
Morgana meets the two new island guests and immediately sets her sights on ‘Ricciardo’, abandoning her current lover Oronte. She takes them to Alcina’s court, where Bradamante is horrified to learn Ruggiero is besotted with Alcina and doesn’t remember his former life with her.
In a jealous rage, Oronte challenges ‘Ricciardo’ to a duel before being broken up by Morgana. Oronte takes his fury out on Ruggiero, revealing exactly how Alcina treats her former lovers.
Alcina plans to turn Ricciardo into an animal to prove her love to Ruggiero. Morgana begs her not to.
Melisso gives a magic ring to Ruggiero, which cuts through the illusions of Alcina’s magic. He is disgusted by what he sees – a desert, populated with monsters. He realises he must run away but is afraid of Alcina’s revenge.
‘Ricciardo’ reveals herself as Bradamante, but Ruggiero believes her to be just another one of Alcina’s illusions. Convinced of Ruggiero’s indifference, both Alcina and Bradamante despair.
Alcina enters to transform ‘Ricciardo’ into an animal, but Ruggiero quickly tries to convince her not to. In this moment, Alcina reveals her true and genuine love for Ruggiero.
Morgana and Alcina realise they are being deceived, but it is too late. Alcina’s power depends on illusion and belief and as her true love is revealed, her magical powers slip away…
Ruggiero destroys the source of Alcina’s magic and the island is both demolished and restored. Animals, rocks and plants all transform back into their human bodies.
Alcina and Morgana are forgotten.