In July of 1942, Anne Frank and her family (her parents and her sister, Margot) go into hiding to escape Nazi persecution of the Jews. They are joined by Mr. and Mrs. van Daan and their son, Peter, and later by Albert Dussel. These eight people hide in the annex of the building in which Otto Frank once worked and are aided by several courageous people who bring them food and supplies and do their best to try to help them. Anne tells the story in her diary, which is published as The Diary of a Young Girl.

Living in secrecy like this is certainly not easy, and there are plenty of problems and challenges. For one thing, the inhabitants of the annex must be completely silent during the day. They cannot make any noise at all, or they risk being heard and discovered by the people working in the offices below. At night, they can move around more, but they cannot use lights, for someone in the street may notice any illumination.

Needless to say, nerves become quite tense under such circumstances, and there are plenty of conflicts among the residents of the annex. Anne and her mother do not get along. Mrs. van Daan continually criticizes Anne. Mr. Dussel and Mr. van Daan sometimes join in on the criticism. The adults get on each other's nerves, too, as Mr. Dussel takes unnecessary risks to get things he wants from outside.

Sometimes the tension escalates into just plain fear as the Nazis drop bombs nearby and as the group worries constantly about being discovered. They can guess what will happen to them in such a case, and it is terrifying. Robberies of the offices beneath the annex also lead to horror among the inhabitants, for they wonder if the robbers have heard them.

Further, as the war continues, food and supplies become more and more scarce. The residents of the annex have to be careful how much they use, and this leads to conflicts, too, as people's egos and desires get in the way of what is good for everyone.

Anne and her family and the other residents of the annex were finally betrayed and arrested on August 4, 1944. Anne, Margot, and Mrs. Frank did not survive the war, nor did Mr. and Mrs. van Daan, Peter, or Mr. Dussel. Only Otto Frank remained of the eight inhabitants of the annex.