The campy TV show “Fantasy Island” rebooted as a horror flick? Director Jeff Wadlow (“Blumhouse’s Truth or Dare”) says it isn’t as much of a stretch as you might think. “The ‘be careful what you wish for’ notion is literally the premise of the show,” he says, “and it’s at the core of every great horror movie.”

His “Blumhouse’s Fantasy Island,” out Friday, takes its premise from the old ABC series, which ran from 1977 to 1984. Set on a mysterious tropical island, it features a dapper host named Mr. Roarke (Ricardo Montalbán), who escorted guests into their own tailor-made fantasies.

“The original show was an anthology,” Wadlow says. “It had guest stars who were the leads each week” —  Maureen McCormick, Michelle Phillips, Roddy McDowall, Sonny Bono, Cesar Romero, Annette Funicello and Leslie Nielsen among them.

“I loved the original show,” says Wadlow, 43. “I remember it very well from when I was a kid. It had such a fun, mischievous energy. I love the way the writers played with the audience, the same way Mr. Roarke played with his guests.”

Ricardo Montalban and Herve Villechaize in “Fantasy Island, 1978-1984 (left) and Portia Doubleday and Lucy Hale in Blumhouse’s 2020 “Fantasy Island.”Everett Collection; Christopher Moss

The new film also features Roarke, now played by Michael Peña (“The Mule”), but does away with the best-known character, Tattoo (Hervé Villechaize). “In the last two seasons, Mr. Roarke had a different assistant,” Wadlow points out, so he felt at liberty to create a new assistant character too (played by Parisa Fitz-Henley). He does include other shout-outs to the series for fans: “The Colonial architecture, the seaplane. And we definitely have a character saying, ‘The plane!’ ” — Tattoo’s famous catchphrase.

Beyond that, Wadlow’s film begins with the series structure, but eventually goes rogue.

“On the show, the storylines never crossed,” says Wadlow, who also co-wrote the screenplay. “They would have two fantasies, and it was done in a way that they could be cut into half-hour episodes and sold that way.” His movie, which stars Maggie Q, Lucy Hale, Portia Doubleday and Ryan Hansen, sees several separate stories eventually entwine — but not before each explores its own spin on twisted wish fulfillment.

Lucy Hale, Austin Stowell and Michael Peña in 2020's
Lucy Hale, Austin Stowell and Michael Peña in 2020’s “Fantasy Island.”Christopher Moss

“What we did with each of our fantasies was, we identified a touchstone film, “Wadlow says of the storylines. “For [Hale’s character],  ‘Saw’ was the touchstone. Maggie Q’s story is more of a ‘Butterfly Effect’ or ‘The Shining.’ The Ryan Hansen story starts out almost ‘Weekend at Bernie’s,’ but turns very quickly into a home invasion vibe, like the first ‘Purge.’ ”

Not surprisingly, Wadlow’s favorite TV episodes were the creepiest. “I really remember the one where Roddy McDowall played the devil,” he says. “Also the one where a guest goes back to the Salem witch trials — the ones where the sinister underpinnings are more evident.”

He’s well aware that much of his movie’s audience won’t know it has a TV precedent. And that’s just fine. “You can see the movie without ever having heard of the show and enjoy it,” he says. “But there are a bunch of Easter eggs, because we have such respect for the series.”

He says he’s proud to be working with classic ’70s source material, rather than rebooting something recent: “We’re not just saying, ‘Hey, remember that video game about a hedgehog?’”