When Domenico first meets Filomena in Naples during World War II, he's instantly captivated. Fast forward to the postwar era, they reunite, sparking a passionate affair that lasts for two decades. As Filomena becomes Domenico's mistress, she discovers his intention to marry someone else, leading her to become resolute in her determination to make him her husband. She devises a series of outlandish plans in an attempt to win him back.

In Rome, fascist supporter Emanuele attends a parade commemorating Adolf Hitler's historic meeting with Italian leader Benito Mussolini, leaving his conservative wife, Antonietta, to tend to household duties. Antonietta encounters Gabriele, a liberal radio broadcaster, surprisingly unfazed by the significance of the day. Throughout the day, they develop a deep friendship that profoundly alters their views on life, love, and politics.

In Naples, Adelina sells cigarettes on the black market, avoiding prison by leveraging a string of pregnancies. In Milan, wealthy Anna escapes boredom by pursuing a struggling journalist, but a costly accident prompts her to reconsider the love affair. Meanwhile, in Rome, Mara, a prostitute with a lot of heart, indulges a young priest’s infatuation, leading to hilarious consequences.