A tour of Plummer's famous relish factory ends in tragedy when one of the visitors is crushed against towers of relish bottles and dumped naked into a 200-degree sterilizer. When the dead man is found to be an executive with rival company Fieldway Foods, Barnaby and Scott's investigation uncovers many secrets and lies among the Plummer family. Someone is also trying to frighten matriarch Amelia Plummer. But who feels strongly enough about Plummer's Relish to commit murder?