Is there a character in contemporary crime fiction whose exploits are anticipated more eagerly by sophisticated readers than Hieronymus Bosch, the principled, caring, and competent cop in Michael Connelly’s outstanding series?

Equal parts Philip Marlowe, Lew Archer, and “Dirty” Harry Callahan, with some of the author’s own personality thrown in, Harry Bosch has already ensconced himself in the pantheon of the greatest fictional detectives of all time.

While many of us have our idiosyncratic favorites, and while some authors produce one or two excellent novels with an ongoing character, I can think of only a handful of crime fighters whose adventures are as consistently compelling as Bosch — and none better.

Even the latest book in this distinguished series, “The Overlook” (Little, Brown; 240 pages; $21.95), is a must-read, in spite of the fact that it’s only about half the length of the other dozen books about him.

The original 16-part serial in the Sunday Times was a thinner and somewhat blander version of the published book. Mr. Connelly has added a new character for the hardcover, fleshed out numerous situations to make them richer, and given the plotlines more complexity. Not to say there was anything wrong with the original, but if you somehow were at home every weekend for four months, and remembered what happened from one week to the next, and never missed an issue, and didn’t mind losing the thread of what is a terrifically suspenseful novel — just forget all that and get the book. Whoever had the idea of serializing suspense fiction does not seem to me to have the slightest notion of what creates suspense, or even what it is. Sustaining it for 16 weeks, with seven-day gaps between each episode, is as difficult as finding a good deli in Gaza.

Oddly (again making the point that it is 40,000 words instead of normal novel length), there is no sense it is too short. While some of the character development may not have quite the same depth and texture as in Mr. Connelly’s other books, the extreme tension of the storyline more than compensates.

Here, Bosch has some serious face time with his old flame, FBI agent Rachel Walling, and if you wonder how he’s doing, let’s just say that it’s a good thing he has a successful career. He breaks in a new partner, a rookie named Ignacio Ferras (“call me Iggy,” he repeatedly tells everyone, especially Bosch, who can’t do it because he thinks it lacks dignity).

In the middle of the night, Bosch is called to a crime scene to find that the victim, shot twice, was a well-known doctor with access to the most dangerous radioactive material locked up in virtually all the hospitals in the Los Angeles area. When the cops check, they find that 32 capsules of cesium are missing. This is enough to easily make a dirty bomb that could destroy Los Angeles, which may only be 20 suburbs in search of a city but still doesn’t deserve to be ruined. The FBI shows up to claim jurisdiction, as they insist that issues of national security are more important than solving a local murder.

Harry sends his conscientious young partner to check out the neighborhood and he turns up a kid who witnessed the crime, someone who came on a bus from Canada to find Madonna, bought a map of the houses of the stars, and was hiding in the bushes when Ignazio found him. Everybody’s worst fears come to bloom when the scared teenager says that he thinks he heard the assassin shout “Allah” and another word. Bosch recalls that the black box from a crashed plane on September 11, 2001 recorded one of the terrorists shouting “Allah Akbar” — God is great — at the very last moment. Terrorists! The word, unsaid, raced through the minds of everyone on the scene:

What a world it was, Bosch thought, when someone could draw the courage to pull the trigger on another man by calling out to his God.

Back at the station house, the detectives talk about the murdered doctor who had been forced to his knees, then shot twice in the back of the head.

“Not a good way to go,” Ferras said.
Bosch looked across the two desks at him.
“Let me tell you something,” he said.
“There are no good ways to go.”

I guess you can’t argue with that. But “The Overlook” illustrates the many colorful, frightening, and shocking ways to go, and Mr. Connelly is an expert at describing them all.

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 ottopenzler@mysteriousbookshop.com.