Like many people in his generation, Louie Psihoyos was a landlubber who grew up watching “Flipper” and Jacques Cousteau adventures on television. After National Geographic magazine hired him straight out of college as a staff photographer, his admiration for the intelligence and beauty of dolphins, and for the oceans as an ecological system, grew as he learned how to dive and began to work underwater.

But none of that quite prepared him for the experience of making “The Cove,” an award-winning documentary about the clandestine slaughter of dolphins in Japan that opens Friday. The film is the first that Psihoyos — “rhymes with sequoias,” he says — has directed, and everything about it has been a challenge, from having to make the transition from still photography, to the subject matter itself, to the cloak-and-dagger techniques used to obtain images that range, as Psihoyos puts it, “from the heartbreakingly beautiful to the heartbreakingly sad.”

San Jose Mercury: The passion of ‘The Cove’