Point of Change is a beautiful, gripping, thought-provoking film about two surf explorers who ‘discovered’ a world-class breaker on a remote island. Did they cause its ruin?

In 1975, two Australian surfers thought they had discovered the holy grail: the perfect wave. Kevin Lovett and John Geisel were at the southernmost tip of Nias, a tiny island just to the west of Sumatra in Indonesia. But during their first fortnight of carving up the then unknown right-hand point break at Lagundri Bay, a miraculous gyre that spat the pair out of ridiculously long-lasting barrels, they were hounded on the shore by sinister figures wearing bird-feather cloaks. When one of them, with burning red eyes, came closer, a friendly local explained what the deal was. “He was supposedly discussing how to kill us,” recalls Lovett. “They said they’d come to take heads.”

In a more typical surf film, the discovery of...