Sherlock Holmes takes one of the most famous of all fictional characters, the brilliant but eccentric London detective created in the late 1800s by Sir Arthur Conan Doyle, and turns him into a modern-day action hero.

The setting is still London in the late 1800s, but Robert Downey Jr. plays Holmes as just as much a martial-arts fighter as a brilliant thinker. And Jude Law plays Dr. Watson, Sherlock’s partner, colleague, and writer of Sherlock’s famous cases, as just as much an equal in the martial arts as Holmes is.

To steal a line from somebody else, “This is not your great-grandfather’s Sherlock Holmes.”

In fact, Watson himself may be onto something, because a major subplot in this mess of a movie is that Dr. Watson is engaged and preparing to move out of their digs at 221B Baker Street.

The fault, Dear Audience, lies with the writers and the director, Guy Ritchie, known for his rock-’em, sock-’em modern-day British crime-caper comedies, but most famous for being the recently divorced husband of Madonna.

When the movie opens, Holmes is in a foul mood, and Watson says to Mrs. Hudson, the woman who keeps their rooms as tidy as she is allowed to, “He just needs another case, that’s all.”

The last case that Holmes had and presumably solved was three months ago, but before he acquires a new case, Holmes is invited to dinner in a restaurant with Watson and his fiancee, Mary, who insists that Holmes examine her at the table and tell her what his observations reveal about her.

To say that it doesn’t go well would be the understatement of the 19th century.

Holmes eventually gets a case that involves black magic, a midget, a plot to rule England and to reacquire the United States, and Holmes’s female nemesis, Irene Adler, played by the beautiful Rachel McAdams.

Yes, this movie is more like a James Bond adventure than a story about the Sherlock Holmes we have come to know, love, respect, and admire.

The movie is preposterous, the story is preposterous, the action scenes are preposterous, even the acting is preposterous.

And, unfortunately, the ending has all the earmarks of a sequel in the works.

Sherlock Holmes is a silly deconstruction of the four novels and 56 short stories that we have read and loved.

I’m Dan Culberson and this is “Hotshots.”