It's not the season of good will to all men... The festive month is kicking off in style and Pearl is rushed off her feet with her restaurant, The Whitstable Pearl. She's also busy planning her own family Christmas and providing mulled wine for a charity church fundraiser when Christmas cards begin arriving all over town - filled with spiteful messages from an anonymous writer. Pearl's curiosity is piqued but having pledged not to take on a case at her detective agency before Christmas, she reluctantly agrees that Canterbury's DCI Mike McGuire should take over; poisoned pen cards are after all a matter for the police.