In the first episode of a two-part story, Jessica (Angela Lansbury) is in Ireland, staying at a bed-and-breakfast at Ballynook Castle. Rumor has it that the castle is haunted by the ghost of a murdered woman, and the locals are convinced that the spirt is responsible for the death of a kitchen worker. Suspecting that the victim was murdered by "live" culprits who are searching for a hidden treasure, Jessica follows a trail of clues that may well lead her into a death trap! Rod Taylor and Fionnula Flanagan, both of whom had appeared in previous episodes filmed in Ireland, show up here in different roles.