When her niece Cat travels to a wedding in Italy, Isabel agrees to fill in at Cat's delicatessen. She takes note of a customer named Ian, who is avoiding chocolate--doctors say it's bad for the new heart he recently recieved. Ian is haunted by memories he can't quite place, prompting Isabel to wonder if his new heart may be the cause. Always keenly interested in matters of the heart, Isabel investigates and discovers some rather surprising truths....

Isabel Dalhousie is a philosopher by training, and an amateur sleuth by choice. When a young man falls from a balcony to his death, Isabel does not believe it was an accident. Plunging deep into the shady business community of Edinburgh, she is determined to root out the truth.