o the Lighthouse is divided into three sections: "The Window," "Time Passes," and "The Lighthouse."
"The Window" opens just before the start of World War I. Mr. Ramsay and Mrs. Ramsay bring their eight children to their summer home in the Hebrides (a group of islands west of Scotland). Across the bay from their house stands a large lighthouse. Six-year-old James Ramsay wants desperately to go to the lighthouse, and Mrs. Ramsay tells him that they will go the next day if the weather permits. James reacts gleefully, but Mr. Ramsay tells him coldly that the weather looks to be foul. James resents his father and believes that he enjoys being cruel to James and his siblings.
Time passes more quickly as the novel enters the "Time Passes" segment. War breaks out across Europe. Mrs. Ramsay dies suddenly one night. Andrew Ramsay, her oldest son, is killed in battle, and his sister Prue dies from an illness related to childbirth. The family no longer vacations at its summerhouse, which falls into a state of disrepair: weeds take over the garden and spiders nest in the house. Ten years pass before the family returns. Mrs. McNab, the housekeeper, employs a few other women to help set the house in order. They rescue the house from oblivion and decay, and everything is in order when Lily Briscoe returns.

In "The Lighthouse" section, time returns to the slow detail of shifting points of view, similar in style to "The Window." Mr. Ramsay declares that he and James and Cam, one of his daughters, will journey to the lighthouse. On the morning of the voyage, delays throw him into a fit of temper. He appeals to Lily for sympathy, but, unlike Mrs. Ramsay, she is unable to provide him with what he needs. The Ramsays set off, and Lily takes her place on the lawn, determined to complete a painting she started but abandoned on her last visit. James and Cam bristle at their father's blustery behavior and are embarrassed by his constant self-pity.