With Valentine's Day fast approaching, Persimmon "Simmy" Brown's flower shop near Lake Windermere receives a string of anonymous delivery orders. But each one causes their recipient great distress, and Simmy suspects that the messages they contain mask a sinister intent. Then one of the recipients disappears….
As if that isn't enough, Simmy's friend Kathy turns up, on the trail of her wayward daughter Joanna, who has grown unhealthily close to her university tutor. 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.