Somewhere in the countryside, the kind but poor Nemorino is in love with Adina, a wealthy landowner’s daughter. He hears her read the story of Tristan and Isolde, and decides a love potion might solve his problem.
Suddenly, the dashing airman Belcore arrives. He immediately proposes to Adina, who says she’ll think it over. Nemorino once again tells Adina how much he loves her; she tells him to find someone else.
The entrepreneurial Doctor Dulcamara visits the village, promising his health drink will cure anything. The excited villagers buy it in droves. In private, Nemorino asks him about the elixir of love. Dulcamara makes a special beverage (enriched with Bordeaux), saying it will take effect in 24 hours. Nemorino buys it and gets drunk.
Adina is irritated by Nemorino’s sudden nonchalance, and agrees to marry Belcore. When the date is fixed for that evening, Nemorino panics – the elixir won’t take effect in time.
The villagers celebrate the upcoming wedding, although Adina wishes Nemorino were there. Once everyone has gone, Nemorino asks Dulcamara for more elixir to cause instant results, but has no money to pay. Belcore promises Nemorino cash in hand if he enlists in the air force. Nemorino accepts.
Gianetta, a schoolgirl, shares a rumour that Nemorino’s millionaire uncle has died and left him everything. When the village women see Nemorino, now absolutely plastered on ‘elixir’, their sudden interest convinces him the elixir is working.
Adina tries to persuade Nemorino not to leave with the air force, but he ignores her. Dulcamara tells Adina that Nemorino only enlisted to pay for more of the remarkably effective elixir. Faced with Nemorino’s devotion, Adina accepts that she loves him too.
Nemorino sees Adina cry at the thought of him leaving, and realises she must love him. She tells him that she’s paid Belcore back, freeing Nemorino from the air force. He persuades her to admit her affections, and both celebrate.
As they learn of Nemorino’s fortune, Dulcamara rejoices at his new product, guaranteed to bring love, health and wealth to all.