When the pesky Anna Bunz arrives at Mardian to investigate the rare survival of folk-dancing still practised there, she quickly antagonizes the villagers. But Mrs Bunz is not the only source of friction - two of the other enthusiasts are also spoiling for a fight. When the sword dancers' traditional mock beheading of the Winter Solstice becomes horribly real, Superintendent Roderick Alleyn finds himself faced with a case of great complexity and of gruesome proportions...