https://en.wikipedia.org/wiki/Force_Majeure_(film)#Plot
A Swedish family consisting of a businessman named Tomas, his Norwegian wife Ebba, their young daughter Vera and preschooler Harry stays at a luxury resort in the French Alps. On their second day, they see a controlled avalanche as they are having lunch outdoors on the deck of a restaurant. The powder cloud of the avalanche gives the appearance that the snow is rising and will wipe out everyone on the deck. Tomas, who is filming the avalanche on his mobile phone, panics and runs as the deck quickly empties of patrons, leaving Ebba with their children encased in a dense fog. Patrons return to their tables as the fog dissipates, and no one is hurt.
That evening they eat dinner with one of Ebba's friends, who has picked up an American man for the evening. Ebba tells the story of the avalanche in English, but Tomas insists he did not run away from the table, and in Swedish adds that one cannot run in ski boots. They argue in front of their embarrassed guests. Ebba is angry that he would not admit he ran away from the avalanche, abandoning them. He says he remembers it differently.
Ebba decides she would like a day of skiing by herself. She has drinks with her friend they had dinner with the night before, as the woman says goodbye to another man. Ebba confronts her friend on her adultery, asking her if she loves her husband and children. Her friend says she is fine with having an open relationship with her husband, and that she is happy if he finds a woman to have great sex with, as he is with her. Ebba becomes more insistent, and the friend advises they not argue, and leaves.
Mats, one of Tomas's old friends, joins them at the resort with his young girlfriend, Fanny. They join Tomas and Ebba for dinner in their suite. After dinner and lots of wine, Ebba again recounts the story of the avalanche, to the silent horror of Mats and Fanny. Tomas curls up with Harry to play a video game, and listens to Mats who insists that we are not ourselves in emergencies, naming the Estonia disaster as an example. Ebba says Tomas won't admit what he did. Tomas returns and again insists he has a different perspective. So Ebba fetches Tomas's phone and has the four of them watch the video of the incident. Tomas reluctantly agrees the footage showed someone running, but is silent when Mats speculates that Tomas was running away so that he could come back and dig out his family later. As Fanny and Mats leave, Fanny suggests that she would expect Mats to react in the same way as Tomas. Mats is irritated, and their relationship is changed for the rest of the trip.
Tomas and Mats ride the ski lift in silence. They ski down fresh powder. Mats suggests Tomas try primal screaming, and Tomas does, screaming swear words into the Alps. Tomas later confesses to Ebba that he hates himself, his cowardice, his cheating in games with his kids, his unfaithfulness. He weeps as his children inside huddle and cry together, hearing their parents argue.
On their final day, the family ascends in the ski lift silently. Ebba is concerned about the thick fog. Tomas says he will go first, then the children, then she can follow. Ebba gets lost in the fog, and Tomas briefly leaves the children alone to go rescue her, returning carrying her shortly after. He sets her down, grinning.
As the family and their friends leave the resort by coach down the winding mountain road, Ebba decides the driver is incompetent and demands to be let off. Panic ensues, and Mats takes charge, insisting women and children get off first.
Eventually, all exit the bus except for Ebba's friend, and the group descends the road on foot. Mats and Fanny are walking apart. Ebba asks Mats to carry Vera. A stranger offers Tomas a cigarette, and initially Tomas declines, but then accepts. Harry asks his father if he smokes — he has not during the entire vacation — and Tomas replies that he does.