John Woo famously redefined the Hong Kong action film in the 1980s and '90s with operatic, ultra-violent classics such as The Killer and Bullet in the Head, hardboiled crime sagas with two-fisted, balletic gunplay in lieu of martial arts.

But it was Johnnie To (Breaking News, Exiled) who perfected the genre, ridding it of its incipient comic book aesthetic and infusing it with a darker, more realistic edge. His films about the Triads (Election I and II) are controlled masterpieces of murderous mayhem, Shakespearean in scope and effect.

To, 58, can still surprise: He hangs up the machine guns for his latest entry, Drug War, an ingenious, intricately plotted crime thriller about a group of cops who break up a local drug operation only to find it leads to the heart of one of the most powerful organized crime networks in Asia.

Sure, there are plenty of car chases and gunshots, but Drug War, which is To's first film set - shot in China - is a different kind. A more cerebral entry, it pits the police against their adversary in an exquisitely complex, methodical game of chess.

Sun Hong-Lei stars as Capt. Zhang Lei, a narcotics detective in the gritty industrial city of Jinhai, stuck working small smuggling cases. As the film begins, he's undercover with a group of poverty-stricken travelers who are paid to smuggle methamphetamines and heroin by swallowing as many as 20 or more drug-filled balloons at a time.

The case of his career drops in Zhang's lap when Timmy Choi (the great Hong Kong star Louis Koo), one of the region's most prolific meth manufacturers, accidentally blows up his own lab and ends up in the hospital.

Chinese law is harsh when it comes to drug manufacturers: Producing more than 50 mg of meth gets you the death penalty. Choi agrees to help Zhang target two of Asia's biggest drug barons in exchange for a lighter sentence.

Choi is injured the day before he is supposed to introduce the two moguls, who have never met. What follows is a beautifully coordinated and complicated cinematic cat-and-mouse game: Zhang impersonates one of the crime bosses to lure in the other, then switches back and impersonates the second guy to snag the first.

Drug War is a deeply intelligent, exhilarating and eminently satisfying adult crime story, one of the best thrillers you're likely to see this year.

Drug War ***1/2 (out of four stars)

Directed by Johnnie To. With Sun Hong-Lei, Louis Koo, Michelle Ye, Huang Yi. Distributed by Well Go USA.

Running time: 1 hour, 47 mins.

Parent's guide: Not rated (profanity, violence, drug use, smoking, sexual situations)

Playing at: Ritz at the Bourse

In Mandarin and Cantonese with subtitlesEndText