In the year 1348, a great plague sweeps through Florence, Italy. The disease causes intense suffering and almost certain death. The city descends into panic and chaos. In response to the horror, ten young people abandon Florence for the countryside. The brigade includes seven women: Pampinea, Filomena, Neifile, Fiammetta, Elissa, Lauretta, and Emilia. The young men are Filostrato, Dioneo, and Panfilo. All the young people are attractive, prosperous, and well-bred.

Pampinea, the instigator of the plan to retreat, leads the companions and their seven servants to a villa outside Florence. Pampinea proposes that each day have a different ruler in charge of domestic arrangements and entertainment. After being chosen as the first queen, Pampinea suggests they gather every afternoon to take turns telling stories. Panfilo begins the storytelling with the tale of Ciappelletto, the worst man in the world, who tells blatant lies in his deathbed confession but becomes a saint after his death. After the tenth story, Pampinea chooses Filomena as queen of the second day. From then on, each day’s ruler selects and crowns the king or queen for the next day.

Filomena decrees that the second day’s topic will be people who suffer misfortune but unexpectedly find happiness. The companions walk in the garden, eat breakfast in the open air, and pass the day singing, dancing, and resting. In the late afternoon, they gather to tell stories about the turns of fortune, all with happy endings. For example, Elissa’s tale features Gualtieri, the noble Count of Antwerp, who is first favored by Fortune and then unfairly disgraced. After long years of exile, Gualtieri is declared innocent and restored to favor.

Neifile, queen of the third day, calls for stories about people who achieve their desires through their own efforts. She suggests that they refrain from telling stories for two days, Friday and Saturday, to catch up on domestic tasks and prepare for church on Sunday. Neifile also proposes that they move to a new location. On Sunday morning, right after church, the brigade walks to an elegant palace that has a magnificent walled garden with a lovely fountain and an abundance of flowers, trees, and animals. That evening, they gather at the fountain for their storytelling. All the stories feature people who use their intelligence to get what they want. Neifile tells the tale of Gilette, a physician’s daughter who is in love with a Count. Gilette travels to Paris, cures the King of a malady, and marries the Count as her reward.

Filostrato, king of the fourth day, chooses the topic of people whose loves end unhappily. Filostrato delays the storytelling with a long speech justifying his work as a writer. His companions are annoyed at Filostrato’s requirement for unhappy endings, but they follow his rules. Filomena tells about Lisabetta, who removes the head of her murdered lover Lorenzo, puts the head in a large pot, plants basil in the pot, and waters the basil with her tears. Eventually, Lisabetta dies of madness and grief.

Fiammetta is the queen of the fifth day. To counteract Filostrato’s sad topic, Fiammetta decrees that the fifth’s day’s tales will be about lovers who survive misfortunes and find happiness. On the fifth day, all the stories have happy endings. Filostrato makes amends with a romantic tale about Ricciardo, an eager young man who climbs up to a balcony and listens to the nightingales with Caterina, his lover.

Elissa, the ruler of the sixth day, chooses the topic of prompt retorts and shrewd maneuvers. The stories on the sixth day are short jokes with punch lines. For example, Lauretta tells about an insulting comment a bishop makes to a respectable woman and the even more insulting comment she makes in return. Because the stories are so short, the companions have time to visit a beautiful valley nearby and swim in a clear lake.

On the seventh day, Dioneo, the king, organizes a picnic in the valley. Dioneo calls for stories about tricks women play on their husbands. After a day of enjoying the pleasures of nature, the companions tell short funny stories about women’s tricks. The jokes are at the husbands’ expense. Once again,the storytelling pauses on Friday and Saturday.

For Sunday, the eighth day of storytelling, the queen, Lauretta, requests stories about tricks that people in general play on each other. Fiammetta contributes the tale of Spinelloccio and Zeppa, two lifelong friends and neighbors. Spinelloccio and Zeppa’s wife become lovers. Zeppa discovers their secret. With his wife’s help, Zeppa tricks Spinelloccio into hiding inside a chest. Then Zeppa seduces Spinelloccio’s wife on top of the chest. Zeppa and Spinelloccio resolve the issue by sharing their wives.

Emilia, the ruler of the ninth day, allows the companions to pick any topic they please. She tells a story set in the Holy Land. Two young men, Melissus and Joseph, seek King Solomon’s advice. Melissus wants to know what he must do to be loved. Solomon’s cryptic advice to Melissus means that he must love in order to be loved. Joseph wants to know how he can get his perverse, stubborn wife to obey him. Solomon’s advice to Joseph, again offered cryptically, is to beat his wife.

Panfilo, the ruler of the tenth day, asks for stories about liberal or munificent deeds. In the final story of the retreat, Dioneo honors Griselda, a poor and very beautiful young girl who Gualtieri, a nobleman, marries on a whim. Although Griselda is a perfect wife, Gualtieri decides to test her patience. He pretends to have their children put to death, but Griselda does not chastise him. Gualtieri casts Griselda out of the house and returns her dowry. Griselda bravely accepts the cruel assault of Fortune. In the end, Gualtieri recognizes Griselda’s worth and restores her to her rightful place. The story of Griselda is the last of the one hundred stories told by the friends. After the story ends, they spend the evening singing and dancing. The next day they rise at dawn and return to Florence.