A scientific lab report confirms that tannery runoff has poisoned the Baths' water supply.

Thomas shares the lab results with Hovstad and Billing, who eagerly agree to publish the findings.

Thomas sends a prepared report about the contamination directly to the Baths Committee.

Peter confronts Thomas, furious that the Baths' water was tested without his knowledge or approval.

Peter tells Thomas that fixing the Baths' pipe system will cost too much and close the facility for two years.

Peter threatens to fire Thomas as medical director unless he publicly declares his findings false.

Hovstad refuses to print Thomas's article and instead accepts Peter's statement dismissing the pollution as rumor.

Thomas calls for a public meeting to announce his contamination findings directly to the townspeople.

Aslaksen and Peter conspire before the meeting and quickly vote Aslaksen in as chairman.

Blocked from discussing the Baths, Thomas delivers an angry speech attacking the liberal majority as incapable of independent thought.

Aslaksen calls a vote and the assembled crowd officially declares Thomas an enemy of the people.

Peter arrives at the Stockmann home to formally remove Thomas from his position as medical director.

Kiil reveals he has spent the Stockmann family's inheritance buying devalued Baths shares to trap Thomas into recanting.

Thomas declares the family will not flee to the New World but will stay and fight.

Thomas announces plans to open a new school where Petra will teach his sons and neighborhood street children.

Thomas Stockmann receives scientific proof that the town's celebrated Baths are poisoning visitors through tannery runoff. When his brother Peter, the mayor, refuses to act and threatens to fire him, Thomas turns to the local newspaper to go public — only to be abandoned by his allies under Peter's financial pressure. He calls a public meeting to address the townspeople directly, but Peter and Aslaksen manipulate proceedings to silence him before he can speak about the Baths. Thomas responds with an explosive speech attacking the town's unthinking majority, earning himself a formal vote declaring him an enemy of the people. In the aftermath, Thomas is stripped of his position and his family faces financial ruin when Morten Kiil uses the family inheritance to trap him into recanting. Rather than surrendering or fleeing, Thomas vows to stay and fight, announcing plans to open a new school for the town's poorest children.

The headline events of the Baths contamination scandal.

Billing is eating at the Stockmann house when Peter and Hovstad arrive before Thomas has returned home.

Thomas arrives home accompanied by Captain Horster and his two sons Morten and Ejlif.

Peter criticizes his brother's expensive lifestyle and leaves the family gathering in a noticeably sour mood.

Morten Kiil visits the Stockmanns and dismisses the contamination as imaginary tiny beasts invisible to the naked eye.

Aslaksen visits Thomas and offers support, suggesting a public demonstration to show the compact majority backs the doctor.

Hovstad privately warns Thomas that Aslaksen is a coward and that most people in town are equally spineless.

Thomas visits the People's Messenger office to plan the formal publication of his pollution report.

Petra arrives at the newspaper office to deliver the English story she had agreed to translate.

Petra refuses to hand over her translation after objecting to the English story's dishonest moral message.

Thomas struggles to find a venue for his public meeting until Captain Horster agrees to host it at his home.

A drunk man who tries to voice support for Thomas is ejected from the public meeting twice.

Thomas finds several rocks thrown through the windows of his study by members of the overnight crowd.

Petra arrives home early after being fired from her teaching job following anonymous letters branding her a radical.

Horster arrives at the Stockmann house and announces he has also lost his position as a ship captain.

Thomas chases Hovstad and Aslaksen out with an umbrella after they arrive with a scheme to profit from Kiil's stock purchase.

Before the contamination crisis erupts, the patterns of small-town politics are already visible in the Stockmann household's evening gatherings, with Peter's jealousy and the newspaper men's radicalism on clear display. Secondary characters reveal their true colors early: Morten Kiil dismisses the pollution as fantasy, Aslaksen offers only conditional support, and Hovstad signals he cares more about attacking the establishment than protecting public health. At the newspaper office, Petra's refusal to translate a morally dishonest English story exposes the gap between the paper's progressive pretensions and its actual integrity. As the public meeting unfolds, even a lone drunk who attempts to voice support for Thomas is forcibly ejected, illustrating how completely the majority has been turned against dissent. The fallout ripples outward after the meeting: Thomas's study windows are smashed, Petra loses her teaching post, and Horster is fired from his captaincy for hosting the event. When Hovstad and Aslaksen arrive at the Stockmann home with yet another cynical scheme, Thomas physically drives them from the house with an umbrella, marking his final break with the town's corrupt middle class.

The people and moments behind the main conflict.

Petra returns from her teaching job and hands Thomas a letter from a scientific laboratory.

Hovstad arrives the morning after the lab results, immediately eager to use the pollution as a springboard to topple local authorities.

After Peter leaves the Stockmann house, Katherine begs Thomas to back down and protect the family's security.

Petra pushes back against Katherine's plea, urging Thomas to stand firm and refuse Peter's demands.

Thomas sides with Petra, declaring that the shame of lying about the contamination would be harder to bear than any punishment.

With Thomas gone from the newspaper office, Hovstad and Billing reveal they are using the doctor purely as a political agitator.

Hovstad admits to Petra that he supports her father only because he is attracted to her; she leaves in disgust.

Thomas mockingly puts on Peter's mayoral hat and cane and struts around the newspaper office to ridicule his brother.

Peter convinces Hovstad and Aslaksen that publishing Thomas's report will cause devastating economic ruin for the entire town.

Peter, Aslaksen, Hovstad, and Billing address the public meeting crowd to discredit Thomas before he is allowed to speak.

Thomas compares the rare free-thinking citizens to well-bred poodles and the general population to ill-bred mongrel street dogs.

Katherine receives an eviction letter from the Stockmanns' landlord the morning after the public meeting.

Peter offers to reinstate Thomas as medical director in six months if he signs a statement declaring the Baths safe.

Peter warns Thomas that Morten Kiil will write the entire Stockmann family out of his will if Thomas refuses to relent.

Thomas plans to practice medicine independently among the town's poor, resolved to remain and fight rather than surrender or leave.

The story's pivotal turns begin the moment Petra delivers the lab letter to Thomas, setting off a chain of choices that will remake every character's life. A family argument — with Katherine urging caution and Petra urging courage — forces Thomas to consciously choose truth over security for the first time. Behind the scenes at the newspaper, Hovstad and Billing expose their cynical motivations, and Hovstad's admission to Petra that he supports her father only out of personal attraction destroys any remaining illusion of principled media solidarity. At the newspaper office, Peter emerges from hiding to reveal the financial stakes to Hovstad and Aslaksen, swinging both men decisively against the doctor after Thomas's mockery of the mayor with his own hat and cane makes their falling-out irreparable. The public meeting becomes a showcase for manipulation, as Thomas's speech about mongrel majorities and free-thinking poodles enrages rather than persuades the crowd. By the play's end, Peter deploys family finances as a final weapon while Thomas responds with a written refusal to Kiil and a quiet commitment to building a new life among the town's forgotten poor.