I Capture the Castle depicts the narrative of Cassandra, a seventeen-year-old girl who lives in a dilapidated old English castle with her family in not-so-genteel poverty. Over the course of six tumultuous months, she works to improve her writing talents. She writes entries that are both sharply hilarious and heartbreaking in three notebooks. Her diaries frankly document the huge changes that occur within the castle’s walls, as well as her own first foray into love.