The book is a harrowing memoir of survival and resilience, chronicling the author's experiences during the Holocaust. As a young Jewish boy in Poland, he witnesses the brutal murder of his family by the Nazis and endures the horrors of the Warsaw Ghetto and Treblinka extermination camp. Against all odds, he manages to escape and join the resistance, fighting for freedom and justice. After the war, he rebuilds his life, only to face tragedy again when his wife and children are killed in a fire. The narrative is a testament to the human spirit's capacity to endure and find meaning in the face of unimaginable suffering.

The book is a dramatic adaptation of the original diary written by a young Jewish girl who, along with her family and others, went into hiding during the Nazi occupation of the Netherlands in World War II. Over the course of two years, she records her thoughts, feelings, and experiences in a secret annex of an Amsterdam building. The diary poignantly captures the realities of living in constant fear of discovery, while also detailing the personal growth, aspirations, and everyday life of a teenager in extraordinary circumstances. The narrative ends abruptly when the group is betrayed and sent to concentration camps, with the girl's father being the only survivor. The diary's posthumous publication offers a deeply personal insight into the horrors of the Holocaust and the indomitable spirit of its young author.