Shy Nemorino is in love with the popular Adina. The gathered students listen as Adina reads them the story of the magic elixir that makes Tristan and Isolde fall in love. A gang of ruffians enters and are welcomed by Adina. The boastful Belcore flirts with Adina as Nemorino looks on
in despair. Left alone with her, Nemorino declares his love, but she encourages him to forget about her.
Peddler Dulcamara tries to convince the crowd to buy his magic elixir, which he guarantees is a cure for any ailment. Nemorino asks Dulcamara if he knows about the love potion of Tristan and Isolde. Dulcamara claims to have it, but in an aside reveals that it is not what it seems. He sells it to Nemorino, with the warning that it will take an entire day to take effect. Left alone, Nemorino takes the "potion", which makes him tipsy. Adina enters and he claims that he is no longer
in love with her. Belcore arrives and continues to pursue Adina. In order to test Nemorino, she agrees to marry Belcore in six days. Nemorino, thinking that by then the elixir will have taken effect, remains unconcerned. When word arrives that Belcore’s gang must leave the following day, Adina agrees to marry him immediately. This turns Nemorino’s feigned indifference to despair as the gathered crowd looks forward to the impending wedding.
Dulcamara joins in Adina and Belcore’s wedding celebration. When everyone goes off with the notary for the ceremony, Nemorino enters and begs for Dulcamara’s
help. The peddler offers to sell him more of the elixir to speed the effect, but Nemorino doesn’t have any more money.
Adina has postponed the wedding ceremony. When Belcore discovers that Nemorino needs money, Belcore convinces him to join the army. Nemorino runs off to find Dulcamara with his recently acquired army pay.
The cheer squad, having learned that Nemorino’s rich uncle has just died, gathers to discuss Nemorino’s recent
inheritance. When he arrives, they all begin to flirt with him, which he ascribes to the elixir. When Adina sees this,
she is amazed. Dulcamara tells her about his elixir and offers to sell her some, but she has other ideas. Nemorino has seen Adina’s reaction and immediately
feels happy. Adina enters and tells him about his inheritance and that she has repaid Belcore in order to release Nemorino from the army. Seeing no other sign of affection from her, Nemorino insists that he would rather die a soldier since he is not loved, whereupon she admits that she loves him. Belcore discovers them and is astonished at the turn of events which Dulcamara claims is the result of his magic elixir.