No, your grandma won't recognize this "Sherlock Holmes."

Played by Robert Downey Jr. and directed by mayhem-loving Guy Ritchie ("Lock, Stock and Two Smoking Barrels"), the thin, calculating, well-mannered brainiac in the deerstalker hat has been transformed. Sherlock Holmes is now a dysfunctional, neurotic action hero with a bit of a substance-abuse problem.

Downey's Holmes is still the smartest man in 1891 London, able to dissect almost any situation from the tiniest hint, but he's also hypersensitive to everything around him; the world is a deafening cacophony of clues and information overload.

Think television's Adrian Monk, with a violent streak and a British accent.

About the only thing holding Holmes together is Jude Law's Dr. Watson, who is smart in his own right and quite capable with a sword and a revolver.

Their relationship reminded me of another, and after two days, I figured it out — doctors House and Wilson in the TV show "House." Even to the point where Holmes tries to sabotage Watson's relationship with fetching English actress Kelly Reilly.

The story itself is interesting. Lord Blackwood (Mark Strong), a disgraced noble who dabbles in the black arts, has been executed but refuses to stay dead. Holmes and Watson must uncover a conspiracy and stop a diabolical plot, aided — or impeded by — sleek con woman Irene Adler (a miscast Rachel McAdams), the only female who has ever really intrigued Holmes.

"Sherlock Holmes" easily could have gone the way of "The Wild, Wild West" — down the tubes of wretched self-parody — but the strong performances and snappy banter of Downey and Law give it vigor, and Ritchie keeps the action moving. The film never fails to entertain, and it sets itself up for an obvious series of sequels.

Downey seems to be preparing himself for a lucrative future as both Sherlock Holmes and Iron Man — which should be entertaining but perhaps a bit constricting for one of the world's finest actors.

Rental Recommendation: Guy Ritchie is in his true element directing Jason Statham and Brad Pitt in "Snatch." Grade: B+

E-mail Steve Ouellette at: ouellette1918@gmail.com