In the early 1920s, Howard Roark, a student at a prestigious architectural school called Stanton, is being expelled for refusing to compromise on his design aesthetics. The Dean tells him the board will reconsider the expulsion if Roark would change his designs to include traditional styles, but Roark refuses, saying he has nothing more to learn at the school. He plans to go to New York and work for Henry Cameron, who was once considered a great modernist architect but is now an alcoholic has-been. Roark, who never doubts his own talent or his decisions, is convinced that Cameron is a gifted architect no matter what the world thinks of him.
At Stanton, Roark has lived in a boardinghouse run by fellow student Peter Keating’s mother, and the two young men are polar opposites. Keating is graduating at the top of his class, and has won a scholarship to Paris and also has a job offer from a prestigious New York-based architecture firm run by Guy Francon. While Roark pays no attention to the people around him, Keating is extremely self-conscious and constantly seeks social approval. He is very insecure and asks for Roark’s help with his architecture work, and also for his advice on whether he should choose the scholarship or the job. While Roark is shocked that Keating would need to ask someone else to make his decisions for him, he does give him helpful advice that leads to Keating choosing the job in New York.
Keating ingratiates himself with the partners at his firm, especially with Francon, and schemes his way to the top, even though he continues to be insecure about his work. When the guilt of his manipulative lifestyle catches up with him, he goes to see his girlfriend Catherine Halsey, whom he loves very much. He is surprised to discover that her uncle is Ellsworth Toohey, a famous architectural critic. Keating is desperate to win a prestigious design competition that he believes would cement his reputation as an architect, and he asks Roark for his help with it. Keating also goes to see one of the partners at the firm, Lucius Heyer, with the intention of intimidating him into retirement so Keating can be named partner. Keating’s cruel behavior towards Heyer, who is already in fragile health, causes Heyer to have a stroke and die, leaving Keating feeling like a murderer. He does become partner at the firm and also wins the design competition, which makes him very popular. Keating also courts Guy’s daughter Dominique Francon, believing that her beauty and money would add to his prestige, but Dominique coldly refuses him, saying that she would only marry him if she wanted to punish herself.
Meanwhile, Roark has worked for Cameron and earned his respect while also learning a lot from him. Cameron suffers a stroke and retires, and Roark briefly works at Keating’s firm before being fired by Francon for refusing to design a building in the classical style. He then works for another firm, but his uncompromising attitude on his design principles leads to him getting fired once again. Roark gets a commission to build a house for the newspaper columnist Austen Heller, who likes his aesthetics, and then opens his own office. However, Roark is eventually forced to close down because he doesn’t get many projects after the Heller house—when he almost gets a commission to build a bank if he’ll add a classical exterior to it, Roark refuses because it is not his design style. He goes to work at a granite quarry in Connecticut to earn his living. There, he sees Dominique Francon, whose father owns the quarry, and the two of them are very attracted to each other. One night, Roark comes over to Dominique’s house and forcibly has sex with her, and leaves without even telling her his name. Soon after, he gets a letter from an entrepreneur named Roger Enright who wants to hire him as his architect, and he leaves to New York City. Dominique can’t stop thinking about Roark but she discovers that he has suddenly left the quarry and does not know how to find him.
Back in New York, Toohey praises Keating’s work in his column for the Banner newspaper, and Keating gets absorbed into a growing crowd of Toohey’s admirers. Dominique sees pictures of the Enright House and is very impressed by it, but she and Toohey agree that it is too good for the world. Austen Heller invites Roark to a party, saying that it might help him get more clients. While Roark initially refuses, he changes his mind when he finds out that Dominique will be there. At the party, Dominique discovers that the man she’d known at the quarry is Roark, and that he designed the Enright House that she admires so much. She makes it her mission to destroy him because his work is so good that she worries the world will corrupt it. She begins to throw parties where she hawks Keating as an architect and steals away the commissions Roark might have gotten. Toohey helps her because he wants to destroy Roark, too, since he detests individualism and talent. Despite Dominique’s actions, Roark completely understands her motivations and doesn’t hold a grudge against her. The two begin to sleep together regularly, though everyone believes they are vicious enemies.
In an attempt to destroy Roark, Toohey plots to have Roark get a commission to build a temple for a religious man named Stoddard. He knows that Stoddard will be unhappy with Roark’s vision, so Toohey sends him away on a long vacation, asking him to return only when the temple is complete. Roark builds a temple dedicated to the human spirit, with a statue of a naked Dominique at its center. When Stoddard returns, he is furious because it looks like no other religious building in the world, and he sues Roark. Dominique tries to defend Roark’s work in the Banner, and ends up getting fired. Frustrated with the world, she tells Keating she is ready to marry him. Keating grabs the opportunity despite knowing they don’t love each other. He abandons Catherine Halsey, whom he had promised to marry. Roark has been financially ruined by the Stoddard temple and doesn’t get any more projects, with the Great Depression looming.
Gail Wynand, owner of the Banner, is looking for an architect and Toohey suggests Keating. Toohey says Wynand should meet Keating’s wife, Dominique, before he makes his decision, and sends him the statue of her from the Stoddard temple. When Wynand and Dominique meet, they instantly like each other—they seem to both value the human spirit and share a love for skyscrapers. Wynand tells Keating he’ll give him the commission in exchange for his wife, and Keating agrees. Wynand and Dominique go on a cruise, where Wynand proposes marriage. Dominique realizes that though she likes him, he runs the Banner, which is a despicable tabloid that had a huge role in destroying Roark. She thinks Wynand would be even worse than Keating—so she agrees to marry him. She finds Roark, who is building a store in a small town in Ohio, and tells him about her upcoming marriage to Wynand. Roark tells Dominique that he can never be with her until she stops letting the world affect her so much, and that he’ll wait for her until then.
Despite her misgivings, Dominique ends up being happy with Wynand. He shares her aesthetics and opinions of the world, but he is more cynical than even she is. In fact, he has made it his life’s mission to prove that no one has integrity by paying off and threatening supposedly honorable people into abandoning their ideals. In the meantime, Toohey is very threatened by the unexpected alliance between Dominique and Wynand, and he is slowly working to bring Wynand down through publications in another magazine called New Frontiers. Dominique warns Wynand about Toohey’s clout at the offices of the Banner, too, but Wynand doesn’t take her seriously.
When Wynand wants to build a home for himself and Dominique, he looks around for architects and really likes Roark’s work. Wynand has no idea that Dominique and Roark were ever together. He approaches Roark for the project without Dominique’s knowledge, and the two instantly hit it off despite Roark expecting to dislike Wynand. Wynand senses that Roark has integrity, and tries to break him into agreeing to never design wonderful, original buildings after building a house for him. He threatens Roark, saying he could destroy his career, but Roark is not intimidated, and the two end up laughing about it. They become friends, and Dominique finds it hard to reconcile herself with this new dynamic.
Keating is struggling as an architect. His firm has lost money and he is considered an old-fashioned classicist while modernism has come into fashion. He is no longer Toohey’s favorite, and Toohey even tells him that the only reason he championed him was for his mediocrity. Desperate for prestigious work, Keating is excited when he hears about the Cortlandt housing project, and begs Toohey to help him get the commission. Keating is not confident in his architecture skills and asks Roark for help designing the project. Roark is intrigued by the challenges presented by the project—which has to be constructed on a meager budget—and he agrees to help Keating if he promises to build it exactly as he designs it. When Toohey sees the designs, he praises Keating’s work even though he knows at once that Keating did not do it himself. Roark and Wynand take a cruise together, but when Roark returns, he finds that the Cortlandt buildings have been completely changed from the way he designed it. So he blows the housing project up.
A scandal ensues, and while Wynand tries to defend Roark in the Banner, he finds that Toohey has completely taken control. He fires Toohey, and as a result, he loses most of his staff, who quit in support of Toohey. Wynand tries to keep the paper going with a skeletal staff and Dominique’s help, but he soon gives up and issues a public apology to Toohey. Dominique is disappointed in Wynand. She finally agrees with Roark that the world does not have any power over them, and she seeks him out so they can finally be together.
Roark faces trial for blowing up the Cortlandt homes. While Toohey’s supporters attack his selfishness and egotism, Roark defends himself and speaks movingly about artistic integrity and the American belief in the pursuit of individual happiness. He is acquitted.
Roger Enright buys the Cortlandt property and hires Roark to build it once again. Wynand hires him to build a skyscraper in Hell’s Kitchen that will symbolize the heights of human potential. Roark and Dominique marry, and she visits him at the construction site, where he stands victoriously atop the steel framework of the skyscraper.