During a performance of La Traviata at La Fenice opera house the distinguished German conductor is found dead, apparently poisoned by a cup of coffee. Brunetti embarks on a voyage of exploration in the often murky world both of opera and the victim's family, eventually unearthing a surprising conclusion.

As Venice braces for a winter tempest and the onslaught of acqua alta - the rising waters from torrential rain - Commissario Guido Brunetti finds out that an old friend has been savagely beaten at the palazzo home of reigning diva Flavia Petrelli

The celebrated soprano Flavia Petrelli returns to Venice after almost 15 years. A reason to be happy. However, her comeback is overshadowed: a boat has been set on fire. The Opera's director is in dispute with the union and blames the latter for several attacks. But when a young costume assistant dies, Brunetti realizes that there is more at stake. When he discovers a hiding place with an observation camera, it becomes manifest: Flavia Petrelli has a stalker! Apparently, the stranger wants to stage her stage performance as an unforgettable event. In return he does not shy away from violence. Is the soprano herself in danger in the end?