The assassin at the center of Cheang Poi-Sou's new thriller Accident is nicknamed "The Brain" (Louis Koo) and the pedestrian title sums up his demeanor – ever-present, calculating, brilliant, and unfeeling. When his wife, seen in flashbacks, was fatally injured in a car wreck, Brain took it that someone wanted her dead and orchestrated all the events that caused the wreck; a cruel or indifferent God never crosses his mind. In other words, the concept that gives the film its title means nothing to Brain. It's unclear exactly how long Brain has been setting up his particular brand of death -- absurdly complex, rigorously planned fatalities made to look like accidents -- or, for that matter, if his thoughts on his wife's death were a byproduct of his system or the spark that lit the fuse. The film opens magnificently as one of Brain's set-ups unfolds: Diverted and rerouted to be in the middle of a sidewalk when a shower of window shards cuts him up, a Yakuza boss bleeds to death while the ambulance is gridlocked, thanks to Brain's associates. These "accidents", chilling in their (generally) flawless execution, are elegant in comparison to the "magnifying glass vs. ant" deaths that populate the Saw series. Brain's calculations are so tightly arranged that even the sway of meteorology comes into play. So when Fatty (Suet Lam), his most reliable associate, is hit by a bus and killed in the middle of a rain-soaked set-up, Brain immediately assumes that he now has a rival. A nervous client leads him to Chen (Richie Ren), an insurance man with an icy, contemplative way that Brain takes as kinship. Borrowing heavily from paranoid thrillers of the 1970s, such as Francis Ford Coppola's The Conversation, Accident morphs into a sort of observational mystery as Brain begins to bug and routinely follow Chen, who may be responsible for a suicide and the near-death of Brain's remaining associate. Pou-Soi made his name in 2006 with the dark, snarling thriller Dog Bite Dog, about a Cambodian assassin on the run from the police, but spent the years before serving as an assistant director for the likes of Ringo Lam, Lau Wai-keung and Johnnie To. His approach to action and tension are similarly riveting, but the director lacks a distinct style in the vein of a bold formalist like To, who serves as producer here. The deus-ex-machina that interrupts Brain's final "accident" throws an appropriate wrench in the works, but it's executed with a noticeable lack of restraint. The filmmaker ultimately feels more beholden to his philosophical underpinnings than to form or, for that matter, to the deeply disturbed Brain. It would be wrong, however, to disregard such well-calibrated action as Pou-Soi offers, especially during an exceptionally disquieting first-quarter dry spell. How wonderful it would be if some of these January-March clunkers -- Legion, The Book of Eli or even Guy Ritchie's flaccid Sherlock Holmes -- studied the exceptional thrillers that China, Korea and Japan have been turning out the way Pou-Soi so carefully mimics The Conversation. The more likely scenario is that an American studio, as headstrong as a self-righteous teenager, will buy the rights to Accident, dissemble it, and recreate it in their own CGI-addled image. Aka Yi ngoi.