The story concerns Frankish soldiers on a Crusade in the Holy Land. The hero Rinaldo gets distracted from his quest by Armida, the daughter of the King of Damascus. She uses her evil spells to seduce him, and two of his comrades have to enter her magic garden to bring him to his senses and rescue him.
At the end of the opera a Chorus of Demons announces that
Armida is going to Hell. (less info)