O'Horten is a picaresque tale about Odd Horton, a dependable and contained train engineer who is retiring after 40 years of service and living a simple life in Norway. His idea of adventure is flying from one city to another.
On the night of his retirement dinner, Odd experiences a series of dislocating events that challenge his routine. He sits by a boy's bedside until he falls asleep, misses his last run due to misadventure, witnesses an arrest, assists an old man and makes a friend, takes a trip with a blindfolded driver, adopts a dog, reflects on his life at the roundhouse, and revisits his mother's disappointment in him.
The central question that arises for Odd is how he should live the rest of his life now that he is retiring.