Review: Documentary ‘A River Below’ reveals murkiness of best intentions

“A River Below” serves as a revealing reminder that you can’t always judge an eco-doc by its cover.

At first glance, the environmental film would appear to concern the efforts of two conservationists to bring attention to the plight of the pink river dolphin, an Amazonian species on the brink of extinction as the result of government-sanctioned hunting practices and mercury poisoning.

While illegal in Brazil, Colombia still permits the slaughter of the dolphins, whose carcasses are cut up as bait for the piracatinga, a type of catfish popular with consumers despite the elevated health risks.

But whatever may have been director Mark Grieco’s initial intentions, the production takes some unanticipated turns away from the conventional “Save the Dolphins!” rallying cry as he follows the activist pursuits of Colombian marine biologist Fernando Trujillo and Richard Rasmussen, a reality TV personality dubbed the Brazilian Steve Irwin.

As Grieco digs a little deeper, speaking with a group of concerned fisherman who have been unfairly implicated in and affected by the resulting media exposés, he discovers that there’s a whole layer of ethical ambiguity lurking beneath the whistle-blowing, however well-intentioned.

Vividly photographed by René Diaz and adroitly edited by Dan Swietlik, “A River Below” skillfully — and quite compellingly — navigates the murky complexities of contemporary reality filmmaking.

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In English and Portuguese with English subtitles

Not rated

Running time: 1 hour, 27 minutes

Playing: Laemmle Music Hall, Beverly Hills

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