Cassandra Mortmain lives with her impoverished family in a crumbling castle. Her journal records her life with her bored sister Rose, her stepmother Topaz, her little brother Thomas and her novelist father who suffers from a financially crippling writer's block. However, all their lives are turned upside down when American heirs to castle arrive.
This enchanting novel tells the story of seventeen-year-old Cassandra and her unusual family who live in not-so-genteel poverty in a ramshackle old English castle. Cassandra's eccentric father is a writer whose first book took the literary world by storm but he has since failed to write a single word and now spends his time reading detective fiction. Cassandra's sister, Rose, despairs of her family's circumstances and determines to marry their affluent American landlord. She is helped and, sometimes, hindered in this by their bohemian stepmother, an artists' model who likes to commune with nature. Finally there is Stephen who is hopelessly in love with Cassandra. Amid this maelstrom Cassandra hones her writing skills, candidly capturing the events that take place within the castle's walls, and her own first descent into love.