By its Cover by Donna Leon (Atlantic Monthly Press, $26)

The 23rd Commissario Guido Brunetti mystery is a must for bibliophiles. Brunetti practices his craft in Venice, Italy where he is hugely outraged by the human depravity and conspicuous corruption he constantly confronts in his beautiful city.

Here he is called in to investigate the theft and depredations committed on rare books at a small but prestigious Venetian library. There are many echoes of the 2012 theft and vandalism that occurred at the Girolamini Library in Naples where its director systematically stole thousands of rare books.

Brunetti finds rare books missing and others where single pages of maps and illustrations have been sliced out. As one of Brunetti's colleagues puts it. "It would make a stone weep." Brunetti has trouble understanding the loss of value caused by an excised page. He learns that a rare book with one illustration gone loses half its value. He is bemused that if the text is intact, that there is little loss of the knowledge itself, why then is the book so greatly devalued. Brunetti is not a collector, and has little or no understanding of the forces that drive the urge to collect. He spends the entire investigation, like the proverbial Diogenes, looking with his lamp for the true book collector and what moves him.

This is a fine puzzle but the real joy is watching a man for whom knowledge is important but not the covers within which it is housed work out the various motives that drive the librarians, patrons, donors, collectors, readers, buyers, sellers and thieves to that most precious artifact - the rare book.

The cherry on top is a wonderful recipe for an artichoke appetizer that this reviewer salivated over at first reading.

To visit the author's web site, see:www.donnaleon.net