They gather four times a year, always as night falls, always at a different location and by invitation only. The topic is usually murder, though it ventures just as easily into kidnapping, torture, poisoning or armed robbery.

One member of this group is a best-selling author, another is a grape grower. A retired professor, a real estate agent, a journalist, and a surgeon are also among its members. Add a suspicious butler and you might have a game of Clue.

Calling themselves the Napa Valley Napoleons of SH, this group has been meeting since 1984 to discuss, toast, argue about, read papers on, present slide shows about, and otherwise celebrate their admiration for Sherlock Holmes, whom they call, simply, the Master.

Sherlock Holmes, the fictional detective of 221B Baker Street, with his colleague, Dr. John H. Watson, forever dwells in the bygone London of impenetrable fog, gas lamps and wicked deeds committed by criminal mastermind Professor Moriarty.

Although to attend a meeting of the Napoleons, it would be easy to mistake Holmes for a living and breathing Victorian-era crime fighter.

There are rambunctious debates about Holmes' drug habit (he had a penchant for cocaine), about Dr. Watson's love life (was he married twice? three times?), where Holmes spent the three years he simply disappeared, and even the date of the detective's birthday. East Coast Holmesians tend to cite Jan. 6, whereas those in the West Coast school of thought tend toward the April 5 theory, according to Donald Yates, Ph.D., who, with his wife, Joanne, founded the Napoleons more than 20 years ago.

"Of course anyone who believes it's Jan. 6 is pathetically deluded," said Yates with a laugh.

The Yateses, who live just outside St. Helena, created the local Sherlock Holmes appreciation group after moving from East Lansing, Mich., where they had fostered a Holmes group whose members included academics from Michigan State University, where Yates himself was a professor of Latin American Literature.

"Our group here is called the Napoleons in part because when I retired I came to St. Helena. And who else retired to a place called St. Helena?" Yates asks in full tongue-in-cheek professor mode.

Answer: The French emperor Napoleon, who had retirement thrust upon him on the island of St. Helena.

In addition there is a Holmes story titled "The Six Napoleons," and Holmes once referred to his nemesis, the cruel, the cunning, the pernicious Professor Moriarty, as "the Napoleon of crime."

This layering on of ideas is the brick and mortar of the Sherlockian world.

At a recent Napa Valley Napoleons gathering the quiz for the evening -- there is always a quiz -- not only required the ability to recall minute details of the story "The Greek Interpreter," but the answers themselves turned out to be an acrostic that spelled out the title of the story in question.

"This is certainly a group that attracts people who have fun with language and ideas," says Yates.

The Napoleons' quiz is the highlight of the evening for the geekier members of the group (this correspondent included).

For others it may be the chance to enjoy the conviviality and to try new restaurants throughout the northern end of the valley.

In the course of 20 years members have been treated to evenings at Stags Leap Wine Cellars, Guenoc Winery and a host of restaurants.

At nearly each meeting Yates offers an "In Memorium" listing of the restaurants that have permanently ceased operation following a Napa Valley Napoleons function.

"We've closed a lot of restaurants," admits Yates.

Yates himself is specially qualified to run this local society of Sherlockians since he's one of fewer than 200 Baker Street Irregulars (BSI) in the world.

The Baker Street Irregulars meet each year in New York City, as close as possible to Jan. 6, the favored date for the Master's birthday in that part of the world.

The BSI organization was founded in 1934 by the author Christopher Morley, best known for his novel "The Haunted Bookshop."

Members have included preeminent authors Rex Stout and Isaac Asimov, as well as honorary members such as U.S. presidents Franklin Roosevelt and Harry S. Truman.

Yates, who has been a member of the BSI since 1972, has countless stories of the whimsical and welcoming feel of these events.

Once while standing in a long line for the men's room following a Sherlockian lunch in New York, someone challenged Asimov, the famous sci-fi author, for an on-the-spot limerick. (Asimov was beloved for his extemporaneous limericks.)

The challenger started with the lines:

"It was a most perilous time

The men were all standing in line ... "

During a pause from Asimov, Yates, who stood next to the famed author, finished with:

"You can take heart

That's a pretty good start

But the first two lines really don't rhyme."