How It All Goes Down
Margaret Hale might not be rich, but she's very well educated and she lives a peaceful life in the hamlet of Helstone. Unfortunately, her father (a pastor) decides one day that he can no longer serve the Church of England because he doesn't agree with its views on God anymore. For the sake of his conscience, he sacrifices his family's peaceful life and moves them to the industrial Northern English town of Milton, where he gets work as a tutor. What a drag.
At first Margaret is grossed out by the filthy, smoky factory town. But over time, she learns to sympathize with its factory workers and their struggling families. She has a harder time, though, sympathizing with Mr. John Thornton, a pupil of her father's who also owns one Milton's main factories.
Thornton has made himself rich with hard work and intelligence, and he believes that he has the right to pay his employees whatever wages he wants. Margaret thinks that he has a moral obligation to pay the workers as much as he can. Conflict alert!
A workers' strike sweeps through Milton. A pack of rioting workers goes to John Thornton's house to threaten him with violence. Margaret stands up for John and uses her body to shield him when the mob starts throwing rocks. Margaret takes a rock to her dome. While she's unconscious, John realizes that he loves her—nothing like a little physical threat to awaken those passions. He proposes to her (after she's woken up) but Margaret rejects the proposal. This leads to bad blood between Margaret and John's doting mother.
Meanwhile, Margaret's mother falls terminally ill. Blame the pollution of Milton. Margaret's brother Frederick has been exiled from England for a mutinying back in his Navy days… if he sets foot in England again he risks getting hanged. Yikes. But Margaret and her father sneak Frederick back into the country to be at his mother's bedside for her death.
Once she has died, Margaret escorts Frederick to the train station to help him get back out of the country without being noticed. On their way to the station, they pass John Thornton, who jealously assumes that they're lovers. They also run into a dude named Leonards who wants to hand Frederick over to the authorities for a reward. Frederick pushes him down, and Leonards later dies. He doesn't die because of the push, though: he dies because he's a drunk and has alcoholism-related organ failure. The police come to Margaret, though, because she was seen at the train station with Leonards and a mystery man (Frederick). Margaret lies and says she was never at the train station. Way to perjure yourself, Maggie.
The police also talk to Thornton, who backs up Margaret's story about not being at the train station, even though he clearly saw her there. He does this because he doesn't want to dirty her good name: it would be assumed that Margaret was out late at night with a boyfriend, and nice girls in the 19th Century did not go out late at night with their boyfriends. This shows us that Thornton is super-loyal to Margaret.
Thornton has also become more of a supporter of his workers. He is trying to support their rights and starts doing things like serving lunch at the factory and eating with the workers. Margaret is starting to realize that she might be a little stuck-up.
Soon afterwards, Margaret's father dies. Margaret is taken under the wing of her godfather Mr. Bell, but she moves back to London to live with her cousin's family. Then Mr. Bell dies. Sadness. It turns out, though, that Mr. Bell was fairly well off and he left her a good chunk of money. Gladness!
Mr. John Thornton visits London later on because some bad business deals have caused him to lose his factory. He's no longer the boss and will have to go back to being a worker. Margaret offers him enough money to keep his factory afloat. And now, at the end of the book, they decide they really do love one another. They get married, even though they know their in-laws will hate them. Aww.