A skeptical journalist finds her rational worldview dismantled when a past-life regression session forces her to inhabit the consciousness of a medieval noblewoman. Jo Clifford intends to write a critical exposé on the validity of hypnosis, but the experiment yields an unexpected, visceral connection to Matilda, Lady of Hay. As Jo navigates the political volatility of King John's reign through Matilda's memories, she discovers that the past is not merely history but a recurring cycle of betrayal and desire. The narrative alternates between Jo's contemporary investigation and the high-stakes survival of the thirteenth century, creating a dual-timeline structure that forces the protagonist to confront the echoes of a life she does not recognize as her own.

This novel is widely recognized as a foundational work in the time-slip genre, noted for its successful blending of meticulous historical research with supernatural intrigue. Readers often highlight the author's ability to maintain tension across two distinct centuries, creating a sense of urgency that bridges the gap between the modern protagonist and her medieval counterpart. The book's enduring popularity is evidenced by its multi-million copy sales and its status as a staple for those interested in the intersection of history and reincarnation. The narrative's atmospheric quality and the emotional stakes of Matilda's plight remain the primary drivers of its sustained appeal over several decades.