I have been drawn to this series as this is the fourth "Zen Mystery" I have read recently. For any readers new to these books all the installments are available except "Cabal", which Amazon shows scheduled for release next month. Nothing I have read so far has suffered from my out of sequence start, but as in any series there are references to prior events that would make the reader more comfortable with the history of the character, if known. The Author Michael Dibdin gives at least a sketch of what has happened if not the details, so starting with the most recent book, as I did, was still very enjoyable.
"Dead Lagoon" brings the protagonist back home, to the City of Venice, the Zen Family house, and a Venice in political turmoil that welcomes only those Venetians that meet their criteria. While this book continues the investigative mystery that is the core of these books, Mr. Dibdin coils a second plot line that is politically based in to the narrative. While it is not as distinct an element, the latter half of 20th Century Venetian History is also intertwined.
The subsequent books will tell, but I believe this is a turning point in the development of Aurelio Zen. As he has in the past he winds up in the middle of a crime, but the practical realities of right and wrong, are blurred by who the victim is, what childhood friends are involved, and other issues long thought to be laid to rest that come back to make Zen's world even more chaotic. And as in the other works, Zen is forced to deal with his Mother who has no use for anyone or anything, when her boy leaves her alone in Rome.
Different from the others I have read, but still very worthy of the time spent.