Joy and happiness prevails in Arcadia - the land of nymphs and muses, only Galatea is saddened, her heart longs for her beloved Acis. Acis roves forests and mountains looking for his Galatea. Unable to find her, in despair he pleads the god of mountains to help him. Damon tries to divert Acis' mind from Galatea, by telling him that love brings but worries and Acis is doomed to ruination if he looses his head for love. Acis disobeyed Damon's advice and meets Galatea. They are happy. Nymphs and shepherds rejoice. Happiness rules in Arcadia.

The chorus warns the lovers of the danger - their joy is over, disaster looms. Cyclops Polyphemus arrives who pines in love for Galatea. He addresses Galatea and invites her to join him at his castle in the rock. Galatea refuses. The furious Polyphemus is ready to take her by force. Damon advises Polyphemus not to attack Galatea but win her with tenderness. Acis, enraged about Polyphemus' love is prepared to defend the dignity of his beloved. Galatea attempts to dissuade Acis but it is too late - Polyphemus crushes Acis with a large rock.

 

The chorus announces mourning. Galatea grieves, the chorus comforts her and suggests using a magic power to save her beloved. Galatea follows the advice and turns Acis into a steram, thus saving him from death in disgrace. Acis is resurrected, happiness and joy rules in Arcadia again.