Lights rise on the interior Dr. Thomas Stockmann's house. It is simple but neat. We can see the living room, and behind it a door opens into the dining room.
Currently Billing, a newspaperman, is sitting at the dining room table, with a napkin tucked under his chin.
Mrs. Stockmann hands him a plate with a big piece of roast beef.
She tells him that he's an hour late so the food is a little cold. They had to go ahead and eat without him because Dr. Stockmann likes his meals on time.
Peter Stockmann, the Mayor, enters the living room. He greets Mrs. Stockmann as his sister-in-law.
She offers him some roast beef too.
He declines saying hot meat late at night gives him indigestion. Tea and bread treat his tummy better at night. Also, it's more economical.
Mrs. Stockmann asks him not think of her and Dr. Stockmann as extravagant.
She tells the Mayor that the Doctor went for a walk with their sons, and will be back before too long.
Hovstad, the editor of the newspaper, enters.
The Mayor assumes Hovstad is there on business, because the Doctor often publishes articles in the paper.
Mayor Stockmann goes on to talk about how he doesn't begrudge his brother, Dr. Stockmann, for writing articles in Hovstad's newspaper.
The Mayor says that the town is very tolerant of contrary opinions. (We get the impression that the newspaper is a little more progressively minded than the Mayor would like.)
The town's splendid sense of community comes from the fact that they are united behind one common interest: the Baths.
The Mayor says that the new Baths will soon become the center of the town's municipal life. Money has really started to pour in since the Baths have been built. Life has gotten a lot better since so many ill people have come to experience the healing power of the Baths.
The Mayor hopes they'll have a good season this summer, with many visitors who will help spread the fame of the Baths.
Hovstad says the Dr. Stockmann wrote an article last year that details the Baths' excellent health record and recommends them to one and all. The Doctor asked that the article not be published for a while, though.
The Mayor wonders if the article was put on hold because of some concern he wasn't aware of.
Hovstad says no. Spring just seemed like a better time to publish the article, because that's when people start planning their summer vacations.
Mrs. Stockmann comments that her husband is always on top of it when it comes to the Baths. The Mayor says that his brother ought to be since he's on the staff. And especially since Dr. Stockmann started the Baths to begin with, Hovstad adds.
The Mayor gets a little offended and points out that had he also lot to do with the creation of the Baths.
Hovstad recognizes that Mayor Stockmann organized the whole thing, but that it was his brother, Dr. Stockmann, who had the original idea.
The Mayor gets even grumpier and says that his brother has all kinds of ideas, but doesn't have the practical mind to get things done.
Things get awkward and Mrs. Stockmann asks Hovstad if he'd like to go inside and eat.
Hovstad goes into the other room.
Peter whispers to his sister-in-law that people of a lower-class background, like Hovstad, never seem to outgrow their crass upbringing.
The jolly Dr. Stockmann enters.
He brings a man named Captain Horster in with him and announces that his wife will have another guest for dinner.
Eylif and Morten, the Stockmanns' young sons, enter.
Dr. Stockmann ushers the boys and the Captain into the dining room.
Mrs. Stockmann points out to her husband that his brother is here.
The Doctor greets his brother cheerfully, as asks if he'd like a drink.
The Mayor declines, saying he doesn't like drunken parties.
The Doctor says it's not a party at all. He just likes having young people around. He likes to see them eating and building strength. They'll need their strength to stir society up and keep things moving.
The Mayor tells his brother he doesn't think society needs stirring up.
Dr. Stockmann comments on how great a mood he's in today. He's just so happy to be around lots of people again after all those years being isolated up north.
He asks his wife if the mail has come, then continues on to say that he's also happy that he's finally making a good salary. It was really difficult trying to support his family on the low salary he was making before.
He shows off all the nice things he's been able to provide for his family recently: a tablecloth, a lampshade, some delicious roast beef.
The Mayor insinuates that his brother squanders his money.
The Doctor replies that he just loves having people over. He felt so isolated all those years in the north. He loves being around all these liberal-minded people.
The Mayor asks his brother about the unpublished article on the Baths.
Dr. Stockmann says he'd prefer the article not be published right now, and that he doesn't want to discuss why.
The Mayor is suspicious and implies that his brother is doing something underhanded.
The Doctor assures him that he's not doing anything bad.
Mayor Stockmann, getting angry, lectures that his brother has too much of an independent spirit, and should learn when to subordinate himself to the greater good.
The Mayor leaves in a huff.
Dr. Stockmann asks his wife again if the mail has come.
Hovstad, Billing, Captain Horster, Eylif, and Morten all enter from the dining room.
Hovstad comments that the Mayor was in a bad mood.
Billing it says it's because he and Hovstad were there, and the Mayor's not a big fan of their newspaper, The People's Herald.
Dr. Stockmann says they should lay off his brother. The Mayor is a lonely guy and only lives for his work.
The Stockmanns bring out alcohol and cigars for all.
The Doctor asks Captain Horster if he'll be sailing for America soon.
Yep, says the sailor.
Billing observes that Captain Horster won't be around for the next local election. The Captain says that he doesn't pay attention to local politics anyway.
Billing comments that society is like a ship that everyone must help steer.
Dr. Stockmann asks Hovstad if there will be anything interesting in tomorrow's paper.
Hovstad says there won't be, but that he wants to print Dr. Stockmann's article in a couple of days.
Dr. Stockmann asks him to hold off on that for a little while, but he still won't explain why.
Petra, the Stockmanns' daughter enters.
She jokingly scolds them all for sitting around enjoying themselves while she's out slaving away.
Billing eagerly offers to make her a drink. She declines, saying he makes them too strong.
Petra says she has a letter for her father.
Dr. Stockmann gets all excited and runs up to his room with the letter.
Hovstad asks Petra if she was teaching at the night school. She says yes.
Billing observes that she taught at the Institute in the morning for four hours. Five, Petra corrects him.
Mrs. Stockmann says that Petra has brought home tons of her students' workbooks to grade.
Petra talks about how tiring it is to be a teacher, but that it's a good sort of tired.
Her little brother Morten tells her that she must be wicked, because wicked people have to work hard as punishment for their sins.
Eylif tells Morten that he's stupid for believing something like that, and Billing laughs.
Hovstad asks Morten what he'd like to be when he grows up. The boy says he wants to be Viking so he can do whatever he wants.
Eylif tells his brother that would mean he'd have to be a heathen (non-Christian). Morten retorts that he'll just have to be a heathen then.
Mrs. Stockmann is extremely uncomfortable with this kind of talk and tells the boys it's time for bed.
Petra tells her mother that she shouldn't get so upset about such things.
Petra goes on to talk about how she's tired of all the hypocrisy around her. At home you can't say what you really mean, and at schoolteachers have tell lies to children.
Petra says that one day she wants to start her own school so she won't have to be a hypocrite anymore.
Captain Horster offers Petra a room in his house to make into a school, but Petra declines.
Hovstad comments the Petra will probably end up being a journalist. He goes on to ask her if she's finished translating the English novel that he gave her.
She says no, but that it will be done in time.
An excited Dr. Stockmann reenters with the opened letter. He says he's made a discovery and that the letter proves he was right.
It turns out that the water in the town's famous Baths are making people sick.
There were some mysterious illnesses last year that made the Doctor suspicious, so he sent water samples to the University. The letter verifies that the Baths' water supply, which is evidently piped in from a swamp, is full of organisms called infusoria.
The Doctor says that all the pipes will have to be re-laid, because when they were first laid he advised that they needed to have a higher intake, but that no one listened to him. Now he's been proven right.
Dr. Stockmann sends the report detailing his findings and the University's letter to his brother, the Mayor.
Petra asks her father how he thinks the Mayor will take the news.
Dr. Stockmann replies that his brother should be happy that such a crucial fact has been revealed.
Hovstad says that he ought to run an article about the Doctor's discovery in the paper. Dr. Stockmann agrees.
Billing comments that, with this important discovery, Stockmann will be the most important man in town.
As the act comes to a close, everyone toasts Dr. Stockmann.
Stockmann thanks them, and says how wonderful it is to be of service to his community.