TRANSIENT DESIRES probably should have a “satisfaction guaranteed” legend imprinted on the cover. This newly published work is the 30th entry in Donna Leon’s series featuring Guido Brunetti, the quiet and understated commissario of the Italian State Police stationed in Venice.

These books have a tantalizing mystery at their core but are very much character-driven, with Brunetti’s internal dialogue commenting on the people, history, culture, flora and fauna of Venice. This latest installment is somewhat different. While it contains the elements noted above in generous amounts, it adds numerous dollops of suspense while revealing a side to Brunetti that is seldom, if ever, seen in previous volumes.

The book is propelled by a single incident. Two young American women are found outside of a hospital. Footage from a security camera indicates that they were deposited there from a boat by two men who then left the scene. Brunetti and Commissario Claudia Griffoni begin their investigation. One of the victims is badly injured and still unconscious, while the other is able to provide little in the way of identifying the men or telling the officers precisely what happened.

"Leon...keeps each mystery complex enough to compel interest but simple enough that the reader (or, for that matter, the author and characters) never gets lost or bogged down."

A little police work, along with Brunetti’s canny deductive skills, leads the officers to two younger men who have been friends for several years. One is the son of an attorney who recently has begun his own legal practice. The other is in the employ of his uncle, who has an extremely unsavory reputation, though little in the way of convictions. It’s a somewhat unlikely friendship, but there are reasons for it. The treatment of the injured women seems more the result of poor judgment coupled with good intent, or at least the absence of malice.

However, there are two underlying secrets, both of which intertwine unexpectedly with a case involving another branch of Italian law enforcement. Brunetti assists his colleagues, which ultimately causes him to learn about and demonstrate a side of himself that is more than understandable under the circumstances, though he is not comfortable with it at all.

Leon has crafted this fine, long-running series so that one can pick up any volume at any time and be surefooted in their reading. The characters, of whom Brunetti is first among equals, are unique to their setting and purpose, but each has characteristics almost immediately familiar to any reader. Leon also keeps each mystery complex enough to compel interest but simple enough that the reader (or, for that matter, the author and characters) never gets lost or bogged down.

While neither Leon nor Brunetti may be household names, bibliophiles and casual readers alike always seem to have at least a book or two of this series readily at hand and on their must-read list. There is good reason for this, and TRANSIENT DESIRES provides an excellent example of why Leon’s audience remains so loyal after three decades.