LETHAL LEGACY. By Linda Fairstein. Doubleday. February, 2009. 367 pages. $26.

T he magnificent New York Public Library (NYPL) is the number one character in Linda Fairstein’s new Alexandra Cooper novel, Lethal Legacy.

Assistant district attorney Cooper and her police pals — especially the elite homicide detective and Jeopardy-obsessed Mike Chapman — investigate the murder of two women with links to both the New York Public Library and the heirs of Jasper Hunt, a 19th century eccentric who donated his rare book collection to the then young library. Hunt was a business partner of the country’s first millionaire, John Jacob Astor, who helped establish the library. Astor and other wealthy male collectors of rare and ancient books were determined to build a library in burgeoning New York city that would rival those already up and running in the cities of Boston and Chicago.

In 2009 some heirs of the library’s early donors are convinced that their grandfathers’ increasingly valuable NYPL collections should rightfully be their own, their personal inheritances. And someone is stealing from the grand institution.

Lethal Legacy is a page-turning mix of modern day, cutting edge crime-solving technology and gilded age grandiosity. Characters include composites of the heroic DNA scientists who helped identified 9/11 victims and fictional suspects from the game of Clue — Professor Plum in the study with a candlestick; Miss Scarlet in the conservatory with a knife.

Ms. Cooper gets drawn into the case when a young female refuses to cooperate with police about an odd break-in at her apartment. Then a maid dressed to look like her boss, the heiress Minerva Hunt, is found dead in same the apartment. Near her body is an old and unusually bejeweled edition of the priceless Bay Psalm Book, the first book printed in North America. Minerva claims the book is part of her grandfather Jasper Hunt’s NYPL collection.

At the police station Minerva deflects attention by telling Cooper her brother Talbot is “the kind of man who would kill for a book like this.” She also offers a take on the inherited traits of the male line of Hunts: “For generations they’ve all seemed to love the same things: rare books, expensive wine and cheap women.”

Who knew that books are not the only gems to be found at the NYPL? Be it for money or ego, a hunt for the world’s oldest map — a map even the library’s most experienced curators are not sure exists — might be at the root of all the related evil.

When the body of the first woman, who happened to be a conservator of rare maps, is found dead in Bryant Park, just steps from the library, Cooper and company move their investigation past the two grand lions and inside the library itself.

They learn the incongruous ways that rare books are cataloged and visit a basement lab — the toxic workplace of professional conservators who preserve and restore the library’s massive collection.

As hard as it is for Cooper to leave the living, breathing history of the library she’s determined to break ground on an old, cold and vicious murder case by using new DNA tracking technology. She asks a judge to allow what is called a DNA kinship search, a quickly evolving technology that links the DNA of one person to his or her biological relatives — an incarcerated brother, perhaps, whose DNA code is out there somewhere in the massive criminal justice databank.

While she pleads her DNA case inside a courtroom it’s easy to imagine thousands of passersby pausing in awe to consider the enormity of literature, human endeavor and world history that rests inside the NYPL. And for the investigators inside it looks like map collections dating back to a time when concrete and steel were nonexistent in NYC could be tools as valuable as new technology for solving the murders and thefts.

Author Fairstein clearly loves New York city, and in Lethal Legacy she brings it to life in a way those lovers of words, cartography, history and Manhattan will thoroughly enjoy. Vineyard residents will too; she is a seasonal Chilmark resident who always includes a splash of the Vineyard in the series. Perhaps her interest in book and map thievery was sparked by the recent case of E. Forbes Smiley, a convicted book thief with Vineyard connections.

Legal Legacy is the 11th in a series of Alex Cooper mysteries. Cooper is tough, strong, and smart, well educated and worldly. She and her friends are in their thirties and all of them are entirely and supremely accomplished in their fields. Storywise this is a disadvantage because, let’s face it, nobody is perfect — it is flaws and complexities that make fictional characters memorable.

Lethal Legacy is a good Island beach read. If only the rain would stop.

Liz Durkee is a frequent book reviewer for the Gazette.