Traces of Justice review – arresting forensic cop thriller chases the science

Based on the real scientist known as ‘China’s Sherlock Holmes’ this sharp feature has thumping set pieces and knotty puzzles set across 30 years of gripping cases

The latest from Chen Sicheng, prime mover behind the hit Detective Chinatown franchise, offers a disarming mix of propaganda, copaganda and gripping narrative. It’s essentially a portmanteau bio

Within the handsome period framework, Chen follows the science: one era’s crazy innovation becomes commonplace in the next. A rookie Cui (played here by Zhang Yi, ageing up subtly) uses boiled potatoes to take dental imprints; when these run out, he and his colleagues start biting one another’s cheeks to make their points. (Their scars are a terrific visual gag: scientists literally showing their working.) By the 90s, when Cui is heading a team working out of a vast, well-staffed warehouse, we seem mere moments away from David Caruso’s sunglasses and memorable Who guitar riffs. The forbidding subtext is presumably that, after 50 years of such breakthroughs, there’s no more getting away with it; as one suspect insists: “everyone pays for what they’ve done.”

Yet Chen’s impressively limber storytelling also accommodates thumping set pieces and knotty forensic puzzle-solving. Remaining necessarily alert to key details, Zhang, in a likable unshowy turn, really does look like someone who’s spent long afternoons studying fingernail structure. The character’s personal life soon drifts out of focus, but the wider picture compels: a culture both becoming more baroque in its sociopathy – the bus bombers are an Asian equivalent to Leopold and Loeb – and sharpening its eye. (End titles also cite the centrality of Cui’s work to China’s current surveillance schemes.) Chen is pursuing reassuring closure and creates an arresting, effective feature besides.