There were many good deeds on the storm-battered Hawaiian island of Kauai over the past week. And there was one particularly bad one.

The stage for what Kauai’s prosecuting attorney called an “absolutely despicable” act was set Sunday and Monday when more than two feet of surging rain in 24 hours produced landslides that buried portions of the narrow coastal Kuhio Highway, which snakes across the lush northern reaches of the island.

The landslides and flooded road turned the isolated and usually idyllic community near Haena into an island unto itself, cutting it off from the nearest refuge in the more developed town of Princeville on the other end of the highway.

The only way out was by sea or air.

(Google Maps)

While authorities did their best to move people to safety, and neighbor helped neighbor in the best Hawaiian tradition, one boat crew was up to something else, Kauai prosecuting attorney Justin Kollar told The Washington Post.

At first, they seemed like good Samaritans. The three men would pull their small fishing boat, about 15 or 20 feet in length, up to the shore where people were waiting for evacuation with a few belongings and offer them transportation from Tunnels Beach at Haena to the St. Regis Resort in Princeville, Kollar said.

But then, while still in the water, the men demanded money. “They would get a couple hundred yards offshore,” said Kollar, “and stop and say, ‘by the way, it’s $200 per person. Cash or credit. Pay now, or we’re going to leave you here.’ ”

People paid, he said. “They felt like they didn’t have any choice.”

One visitor, Liana Leaulii, described her experience to Hawaii News Now. She and a group had been hiking along one of the mountainous trails along the coast when the torrential downpour and lightning storm that would continue for 36 hours began. They managed to make it to Tunnels Beach when they encountered the crew with the boat.

With relief, they gladly accepted the ride. But “once we were out in the middle of the ocean, they were like, ‘Did so-and-so on the beach tell you it was $200 a head on the boat?’ ”

“So and so” had told them nothing of the kind.

Kollar said authorities started learning about it on social media. He didn’t have an exact number of victims, but there were more than a few. “We’re still working that out,” he said.

Once the word got out, with Kollar telling local media the men would be charged with extortion, they “laid low,” he said.

“We’re not going to tolerate these type of extortion [attempts] of any visitors or locals, Chief Bryson Ponce of the Kauai Police Department told Hawaii News Now. “And to the people who are doing these things, we’re gonna hold them accountable.”

Kauai resident James Hennessy maneuvers a stand-up paddle board along his flooded street in Haena, Hawaii, on April 15. (James Hennessy/AP)

But people knew who they were.

On Thursday, police arrested Stephen Koehne for extortion, robbery and terroristic threatening, Kollar said. Koehne, who bills himself as a “pirate” on the Internet, could not be reached for comment. It’s unclear what’s happening with the other two men reportedly involved.

The wild weather over the weekend produced dramatic scenes as houses were lifted from their foundations and helicopters and boats evacuated some 340 residents and visitors. (This is the area that served as a backdrop for the classic film, “South Pacific.” Some 17 miles to the east of Haena is the estate of Facebook founder Mark Zuckerberg, who has contributed $1 million to the recovery effort.)

Among the strangest sites was a herd of bison, from a ranch near the town of Hanalei, fleeing in terror into the ocean. Jet Ski cowboys took to the sea with lassos to round them up and tow them to shore, where they were moved to safer ground.

Hawaii’s stunning “garden island” is just beginning the recovery from its worst flooding in decades following the powerful storm that surged through the island.

“It’s an area that is so special to people,” Kollar told The Post. “It’s an absolutely magical place. To have it tainted this way, it’s sad.”

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