Valentine's Day is fast approaching and Persimmon 'Simmy' Brown's flower shop near Lake Windermere is doing good business. But when Simmy receives a string of anonymous delivery orders, each one causing their recipient great distress, she begins to suspect that the messages they contain mask a sinister intent. When one of the recipients disappears, it would seem that her worst fears have been confirmed.

As if that isn't enough, Simmy's friend Kathy turns up, on the trail of her wayward daughter Joanna, who she fears has grown unhealthily close to one of her university tutors. When Kathy attempts to reason with her daughter she finds that Joanna's older lover may be even more menacing than she had imagined. With both Kathy and Joanna in peril, Simmy and her friends find themselves caught up in a web of deception, blackmail and murder. It seems that Simmy Brown faces her most puzzling, and perhaps her most dangerous, case yet.