Identical twin sisters Alex and Hannah are the owners of Murder and Mayhem, a mystery bookshop that sells their famous poison-themed Killer Chocolates. But now, there's a real killer in their midst. Shortly before Christmas, their septuagenarian neighbour, Jane, confides to Alex that a murderer from a true-crime show has taken up residence in the village. Unfortunately, she's also shared her suspicions with town gossip Netta. The next morning, Alex...