Lawrence Ah Mon’s Dealer/Healer tells the true story of Chen Hua (Lau Ching Wan), a drug dealer and drug addict turned philanthropist, from his teenage years in the Tsz Wan Shan district of Kowloon, the start of a lasting friendship with fellow hellraisers Cat (Max Zhang) and Bullhorn (Lam Ka Tung) and of a romance with plucky waitress Kerou (Jiang Yiyan), to his time as a drug dealer in the infamous Kowloon Walled City, where he encountered drug lord Halei (Louis Koo) and reached the nadir of his addiction, and then to his reformed life – following a few years in prison – and his work in a Christian rehabilitation centre, while still mediating mob disputes to limit damage and avoid violence.

The film’s most striking aspect, beyond its starry cast, is its impressive reconstruction of 1970s and 1980s Hong Kong, and especially of the labyrinthine Kowloon Walled City, splendidly rendered in all its shady nooks and seedy crannies by production designer Wang Hui Yin, cinematographer Zhang Ying and vfx supervisor Zhang Zhanrong. It’s an impossibly cinegenic place, and the film is at its most compelling when it’s unfolding there. But the rest of the time, it’s a worthy but slightly dull biopic. By choosing to tell the story in non-linear flashbacks for much of the film’s runtime, one can tell Lawrence Ah-Mon has tried to stir things up in a narrative that could have been rote, despite its inspirational true events. And while it works to some extent, the film simply doesn’t dwell on the transition from dealer to healer long enough to give it a dramatic impact. Most scenes depict him either as a shabby but not irredeemable drug dealer or as a stalwart, magnanimous philanthropist, with few shades in between, and interesting characters and relationships left frustratingly under-developped.

Luckily, a superb ensemble cast is on hand to paper over the cracks. Lau Ching Wan is expectedly excellent as Chen Hua, and his interaction both with the superb Jiang Yiyan, achingly subtle as his long-suffering girlfriend, and with Max Zhang (who impresses in a rare non-fighting role) and the ever-reliable Lam Ka Tung, provides the film with its strongest emotions. It’s always a joy to witness Lau and Louis Koo’s spotless chemistry (now seasoned through fourteen collaborations, with a fifteenth just wrapped), and the latter makes the most of an underwritten role through sheer charisma. Then there’s considerable old-school Hong Kong flavor brought by Ng Man Tat, Chen Kuan Tai, Nora Miao and Lo Hoi Pang who pop in and out of the film for brief but droll or touching vignettes.

Long Story Short: A worthy but under-developped inspirational biopic, rich in period detail and carried by a superb cast. ***