“The darker the underbelly, the prettier the top layer,” says one of the main characters in “G Affairs,” a striking, metaphor-heavy excursion into corruption and moral decay in contemporary Hong Kong. This knockout debut by young director Lee Cheuk-pan revolves around half a dozen people whose lives are connected by a severed head that appears in the film’s breathtaking opening shot. Standing stylistically apart from just about everything else in recent Hong Kong cinema, “G Affairs” picked up a swag of Hong Kong Film Awards nominations ahead of a brief local release in March. Lee’s urgent and vital film ought to enjoy a long festival run, especially in light of recent events that have placed renewed focus on the Special Administrative Region’s immediate and long-term futures.

“G Affairs” is at once a pulpy crime drama and an arresting exercise in experimental storytelling. The film takes its title...