The play begins as Sidi, the village belle of Ilujinle, enters the square with a pail of water balanced on her head. Lakunle, the western-educated schoolteacher, sees her, runs from his classroom, and takes Sidi's pail. He berates her for carrying loads on her head and not dressing modestly, and she retaliates by reminding Lakunle that the village calls him a madman. Sidi grows angry as Lakunle tells her that women are less intelligent than men because of their small brains. He says that soon the village will have machines to do all the hard work and he describes the beauty of Lagos, which is an entirely modern city. Lakunle refuses to give Sidi her pail of water back until she agrees to marry him and he offers a number of flowery lines that describe his intense love for her. Sidi reminds him that she'd marry him any day if he'd agree to pay the bride price. Lakunle deems this barbaric and refuses. He grabs Sidi and tells her how wonderful their modern marriage will be. When he kisses her, Sidi is disgusted. Though Lakunle insists that he loves Sidi and that kissing is something normal for modern couples, Sidi replies that kissing is only a way to avoid paying the bride price. She calls Lakunle mad.
A group of young villagers enter the square and tell Sidi that the stranger returned to the village with a magazine of images. Sidi excitedly asks if the stranger made Sidi as beautiful as he said he would, and the girls tell her he did. They say that Baroka, the village Bale, is still looking at the images and is jealous of Sidi, though he pretends to be proud of her. Another girl says that Baroka appears in the magazine as well, but his image is very small and shows him next to the latrines. Upon hearing this, Sidi declares that she's more powerful than Baroka and has no reason to marry Lakunle.
Sidi suggests that they dance the dance of the "lost traveler." She assigns parts to the villagers and forces Lakunle to play the part of the stranger. Despite his initial unwillingness to participate, Lakunle throws himself fully into the dance. The rest of the villagers dance while Lakunle performs realistic miming of driving a car, drunkenly wandering through the jungle, and discovering Sidi in the river. Suddenly, Baroka joins the dance and the action stops as the villagers kneel and bow to him. Lakunle tries to leave, but Baroka insists he stay and they continue the dance. Baroka instructs his attendants to seize Lakunle/the stranger, but he then takes pity on the stranger and sets out a feast in his honor. The stranger takes photographs of the village and is especially entranced by Sidi and her dancing. The dance ends when the stranger vomits. Sidi and the villagers chase Lakunle towards the actual stranger so he can translate for them, and Baroka muses that he hasn't taken a new wife in five months.
Later that day, Sidi and Lakunle walk down the road. Lakunle carries a bundle of firewood, while Sidi is engrossed in the photographs of herself in the magazine. Baroka's first wife, Sadiku, startles Sidi. Sadiku tells Sidi that Baroka wants to marry her, which makes Lakunle angry. He tells Sidi not to listen, but Sidi insists that she's very powerful now that the stranger has brought her images to the village. Sadiku insists that if Sidi marries Baroka, she'll be very powerful—when Baroka dies, she'll be the new head wife. Sidi refuses and says that Baroka only wants to possess her beauty and keep it for himself. Sidi opens the magazine, shows the photographs to Sadiku, and laments that nobody ever complimented Sidi on her breasts. She calls Baroka old and leathery. Sadiku is shocked, but she invites Sidi to come to Baroka's for a feast anyway. Sidi laughs and says that the women who attend the suppers become wives or concubines the next day. Lakunle inserts himself into the conversation and says that Baroka is called "the fox" for a reason. He describes how Baroka paid off a foreman to reroute a railway away from Ilujinle, thereby robbing Ilujinle of the ability to modernize. He loses himself in thought and muses about how wonderful Baroka's life of luxury with so many wives must be. Sidi and Sadiku slip away.
In Baroka's bedroom, his favorite wife plucks the hairs from his armpit. He tells her that he's going to take a new wife soon and she plucks the hairs harshly. Sadiku enters the bedroom and Baroka sends his favorite away. Sadiku tells her husband that Sidi refused his offer of marriage because of his age. Angry, Baroka lists his achievements of the past week. He lies down, asks Sadiku to rub his feet, and picks up a copy of the magazine. He suggests that it might be for the best, as his manhood ended the week before. Sadiku cries, and Baroka tells her that she cannot tell anyone of this secret.
That evening, Sidi continues to admire the photographs in the village square. Sadiku enters the square, pulls out a carved figure of Baroka, and laughs. She begins a chant of "take warning my masters/we'll scotch you in the end" and dances around the figure. Sidi, shocked, approaches Sadiku and demands to know what's going on. Sadiku swears Sidi to secrecy and whispers in her ear. Sidi is overjoyed and joins in the dance. Lakunle enters the square and watches the women for a moment before deeming them crazy. Sidi suddenly stops and says she wants to taunt Baroka. She decides to go to him, ask forgiveness, and torment him. Sadiku gives her blessing and Sidi runs off.
Lakunle calls the women foolish. Sadiku tells Lakunle he's unattractive and reminds him that he could marry Sidi soon if he paid the bride price. When Sadiku laughs about Lakunle's wish to modernize the village, he insists that she come to school with the children so she can learn to do something besides collect brides for Baroka.
When Sidi enters Baroka's house, he's engaged in a wrestling match with his wrestler. Baroka is annoyed that nobody was there to greet Sidi and keep her out of his bedroom, and he explains that his servants take Sundays off now that they've formed a union. Sidi asks Baroka for forgiveness for her hasty reply. He pretends to not know what she's talking about, throwing Sidi off guard. Sidi asks after Baroka's favorite wife and asks if she was somehow dissatisfied with her husband. Baroka insists he has no time to consider his wives' reasons for being unhappy, which scares Sidi. Baroka asks her to sit down and not make him feel old.
Sidi says that the wrestler will win. Baroka explains that the wrestler must win, as Baroka only fights men who challenge him and he changes wrestlers when he learns how to beat them. Similarly, he takes new wives when he learns how to tire the old ones. Sidi tells Baroka that someone brought her an offer of marriage earlier that day and asks Baroka if he'd consent to allow her to marry this man if he were her father. She describes Baroka and answers his questions about her suitor in such a way as to offend Baroka. Baroka throws his wrestler and Sidi celebrates Baroka's victory. The men begin to arm wrestle and Baroka resumes his line of questioning about Sidi's suitor. Sidi insults Baroka's virility. Baroka wins the match again and sends his wrestler away. He sits down next to Sidi and laments how old he's becoming. He asks if Sadiku invented a story for Sidi, saying that Sadiku is constantly finding new women for him to marry.
Baroka pulls out the magazine and an addressed envelope. He asks Sidi if she knows what the stamp is. Sidi does; she says it's a tax on "talking with paper." Baroka motions to a machine in his bedroom and says he wants to use it to print stamps for Ilujinle with Sidi's face on them. Sidi loses herself in this dream, and Baroka explains that he doesn't hate progress, he hates the sameness that progress brings. He tells Sidi that the two of them are very alike and they fit together perfectly. Sidi wonders if she's dumb like Lakunle says she is, but Baroka says she's simply truthful. He insists that the old and the new must embrace each other as Sidi's head falls onto his shoulder.
In the market that night, Lakunle and Sadiku wait for Sidi to return. A group of mummers passes them and Sadiku suggests they've heard about Baroka. She steals money from Lakunle's pockets and pays the mummers. They dance the story of Baroka's downfall, and Baroka is portrayed as a comical character. Sadiku herself gets to dance the final "scotching" of Baroka.
Sidi runs into the market crying. Both Sadiku and Lakunle try to comfort her, but she won't let them. She says that Baroka tricked them and she's no longer a virgin. Lakunle is angry for a moment, but then says he still wants to marry Sidi and no longer has to pay the bride price. Sidi runs away. Lakunle sends Sadiku after her to find out what she's doing. Sadiku returns and says that Sidi is dressing herself like a bride, and Lakunle insists that he can't get married immediately.
The dancers and Sidi re-enter the square. Sidi is beautiful. She offers Lakunle the magazine and invites him to the wedding. He insists that he must be invited, since he's the groom. Sidi laughs and says she'd never be able to marry him after experiencing Baroka. She asks the musicians to play music while she walks to Baroka's house and the dance begins. A young girl dances suggestively at Lakunle, and he chases after her.