The opera takes place in 21 scenes, with an introduction.
Torquemada is at work in his shop when the muleteer Ramiro stops by to have his watch fixed, so that he can fulfill his duties at collecting the town's post. It is Thursday, the day that Torquemada goes out to tend the municipal clocks, so Ramiro must wait. Torquemada's wife, Concepción, enters to complain that her husband hasn't yet moved a clock into her bedroom. After Torquemada has left, she takes advantage of his absence to plan assignations with gentleman friends. However, the presence of Ramiro is initially a hindrance. So she asks him to move a grandfather clock to her bedroom, which he agrees to do.
Meanwhile, she waits for Gonzalve, a poet. He arrives, and is inspired to poetry, but not to lovemaking, where Concepción would prefer the latter. When Ramiro is about to return, she sends him back saying that she chose the wrong clock. She then has the idea of having Gonzalve hide in one clock so that Ramiro can carry him upstairs. After Gonzalve is concealed, Don Iñigo, a banker and another of Concepción's gentleman friends, arrives. When Ramiro returns, she persuades him to carry up the clock with Gonzalve concealed in it, and she accompanies him.
On his own, Don Iñigo conceals himself in another clock. Ramiro enters, asked to watch the shop, and musing on how little he understands of women. Concepción then summons him back upstairs, saying that the clock's hands are running backwards. She and Don Inigo try to communicate, but Ramiro arrives back with the other clock. Don Inigo has hidden himself again, and Ramiro now carries up the clock with Don Iñigo upstairs.
With Gonzalve now downstairs, Concepción tries to turn him away from poetry towards her, but Gonzalve is too absorbed to follow her lead. Ramiro returns, and Gonzalve must conceal himself again. He offers to take the second clock up again. Impressed by how easily Ramiro carries the clocks (and their load) upstairs, Concepción begins to be physically attracted to him.
With Gonzalve and Don Iñigo now each stuck in clocks, Torquemada returns from his municipal duties. Both Gonzalve and Don Inigo eventually escape their respective clock enclosures, the latter with more difficulty. To save face, they each have to purchase a clock. Concepción is now left without a clock, but she muses that she can wait for the muleteer to appear regularly with his watch repaired. The opera ends with a quintet finale, as the singers step out of character to intone the moral of the tale, paraphrasing Boccaccio:"Entre tous les amants, seul amant efficace,Il arrive un moment, dans les déduits d'amour,Où le muletier a son tour!"
"Among all lovers, only the efficient succeed,The moment arrives, in the pursuit of love,When the muleteeer has his turn!"