"I Capture the Castle" is a classic novel by Dodie Smith, revolving around the eccentric Mortmain family living in a decaying English castle. The story is narrated by Cassandra, the teenage daughter, as she chronicles their struggles, love affairs, and aspirations through her journal entries. It's a charming and witty tale of coming of age and romantic escapades in a unique setting 

Through her journal entries, Cassandra chronicles her quirky family's attempts to escape poverty and the arrival of two wealthy American brothers who disrupt their lives. The novel explores themes of love, growing up, and the pursuit of dreams against a backdrop of humor, romance, and literary charm.