Ten years ago, a woman who was once an assistant district attorney in New York City started to write crime novels about a woman who is an assistant district attorney in New York. Let’s see, do we think the character was based to some degree on the author?

In New York, Rudolph Giuliani and Elliott Spitzer made headlines as assistant district attorneys. With lots of name recognition, they then ran for higher political office. Mr. Giuliani became famous for going after the mob. Mr. Spitzer went on to become attorney general and has become famous for going after businessmen who are either thieves or, it seems, people he doesn’t like. (Just for the record: In New York, there is only one district attorney, and he has been Robert Morganthau since, I think, the day after the Indians sold Manhattan island for 24 bucks. All other prosecutors, and there are 600 of them, are assistant district attorneys.)

Linda Fairstein, the most famous female ADA of all time, chose to go a different route. Having been the head of Manhattan’s Sex Crimes Unit for more than 25 years, she handled some of the highest-profile crimes in the city, including the Central Park jogger case and the so-called Yuppie murder case. Although known to be a cardcarrying liberal Democrat, she was a ferocious pit bull in the courtroom and helped put away the human waste products who committed heinous crimes against women and children.

Ms. Fairstein started to use an entirely new set of skills when she sat down to write a novel. The result was “Final Jeopardy,” published a decade ago, which had so much success that, with the encouragement of her publisher, she kept at it. The eighth installment of what has become a bestselling series was published yesterday, and it may be the best of the bunch. In this one, “Death Dance” (Scribner, 402 pages, $26), ADA Alexandra Cooper deals with two cases simultaneously, both of which are fascinating.

In the first, two young women claim they were drugged and raped.Tourists from Canada, they accepted the offer of a young physician to stay at his apartment.They have made clear that the sleeping arrangements did not include any up-close-and-personal behavior, and they trusted him when he said he had a girlfriend and would probably stay at her apartment anyway.

On their last night in the city, the physician offers the women a drink foamed up in a blender, which causes them to immediately fall into unconsciousness. When they wake the next day, groggy and very sore, they go first to a hospital and then to the police. It turns out the physician is Turkish and, despite Alexandra’s warning that he is a flight risk, a repugnant judge frees the suspect on his recognizance.

In the middle of this fine state of affairs, a prima ballerina disappears from Lincoln Center in the middle of a program.

Ms. Fairstein is a real New Yorker and, in addition to knowing a lot about the city and its institutions, clearly enjoys doing research and dropping in tidbits of her findings. In a previous book, “The Bone Vault,” she gives a nice tour of the Natural History muse um. In “Death Dance,” it is a behindthe-scenes look of the Metropolitan Opera House that fills many pages.

This may not be to everyone’s taste. The action can slow down a little while we learn that there are 400 people backstage at the Met, how the scenery works, precisely what the stage manager does, and so on. I love it, because the information sets the stage (if you’ll pardon the obvious pun) for the activity that occurs, and because the information is dispensed a bit at a time so it never has the feel of a dissertation.

For those who are not law-enforcement professionals, Ms. Fairstein has the smoothest approach to informing readers what the acronyms and abbreviated terms mean. Here’s an example: In dialogue, a cop talks like a cop. He says, “Think we’ve got a DFSA.” The next paragraph begins: “Drug-facilitated sexual assault had been around for a very long time. There were mickeys slipped to femmes fatales in half of the noir films and pulp fiction of the forties and fifties.”

As an ADA who knows a lot about crime, Ms. Fairstein also drops factoids into her books that are not essential to plot development but enhance the reading experience anyway. Did you know, for example, that 18,000 missing-persons reports are filed with the NYPD every year, almost all about people who want to go missing? That is why the policy is for the police to not investigate until someone has been missing for at least 24 hours.

The search for the ballerina begins sooner than that because she’s famous. The police and the DA don’t like negative headlines. Who would, come to think of it? The manhunt leads to legitimate Broadway theaters, including the Belasco, and some people who I hope were not based on real-life characters because they plummet to such a depth of odiousness that one can only hope for them to have bad endings.

A fluid style keeps the pages turning in Ms. Fairstein’s novels, though in “Death Dance” she is guilty of one of my pet peeves. She has a character “hiss”: “Who the hell are you and what are you doing here?” It is not possible to hiss a sentence that lacks sibilants.Yes, yes, it’s nit-picking. And she can be forgiven. After all, it’s not like she decided that, since Robert Chambers was a nice clean-cut looking fellow, he should be allowed to head off to the next keg party.

Mr. Penzler is the proprietor of the Mysterious Bookshop in Manhattan and the series editor of the annual “Best American Mystery Stories.” He can be reached at openzler@nysun.com.