Following the death of her parents, Miss Cassandra 'Cassie' Richards returns to England, and accepts Lady Royce's invitation to Cornwall.
Upon arriving at the 500-year-old Royce Castle complete with secret rooms and friendly ghosts, Cassie encounters Lady Royce's son Phillip, the bookish and painfully reserved Earl of Royce.
A man of logic and order, Phillip has no patience for Miss Cassandra's frivolous notions of ghosts and hauntings.
Fortunately, there're a couple of loving spirits willing to give the couple a helping hand.