what is the plot of the story

Mrs. Ramsay, Mr. Ramsay (a philosopher), their eight children, and several guests are staying at the family's summer home in the Hebrides, on the Isle of Skye, just before the start of World War I. Just across the bay is a lighthouse, which becomes a prominent presence in the family's life. James Ramsay, the youngest child, wants to go to the Lighthouse the next day, but Mr. Ramsay crushes his hopes, saying that the weather will not be pleasant enough for the trip. James resents his father for his insensitivity as well as for his emotional demands on Mrs. Ramsay, and this resentment persists throughout the novel.

Just check out this short summary from GradeSaver and you will be able to see the sequence of events,

http://www.gradesaver.com/to-the-lighthouse/study-guide/short-summary/