After a supernatural showdown with a serial killer, Evie O'Neill has outed herself as a Diviner. Meanwhile, mysterious deaths have been turning up in the city, victims of an unknown sleeping sickness. Can the Diviners descend into the dreamworld and catch a killer?

Paintings have been falling off of walls, a loud and loyal dog has gone missing, a specter has been seen walking the pier at midnight; strange things are happening all over the town of Stain'd-By-The-Sea. Called upon to investigate thirteen suspicious incidents, young Lemony Snicket collects clues, questions witnesses, and cracks every case.