Since she was a child, Katie Ennis has loved hearing ghost stories. Now she’s telling one of her own. The filmmaker, a graduate of Boston University, is headed to the Isles of Shoals off the coast of Portsmouth, N.H., next month to film her first short horror film, called “Haunted.” The story follows a young couple’s weekend adventure at the fictional Ocean Manor Hotel, and Ennis (inset) is using the whitewashed Oceanic Hotel on Star Island as the creepy setting for the ghostly tale. “They say pirates used to stop there, that Blackbeard abandoned one of his wives [there],” said the 28-year-old, who also wrote the “Haunted” script. Based in New York, Ennis has worked as a film and TV editor. (Her credits include USA Network’s “Royal Pains” and “Hits,” which premiered at Sundance earlier this year.) “I’ve had a lot of success in my editing career. I’ve always wanted to work on stories of my own,” she told us. “The doors have just kind of opened to see if I can make it happen.” Helping to make “Haunted” happen is Fractured Atlas, a nonprofit that has partnered with Ennis for an Indiegogo campaign to fund the film. Regardless of what she raises, Ennis will bring her all-Gotham cast to the Oceanic, which was featured on Syfy’s “Ghost Hunters.” The cast for “Haunted” includes indie actress Genevieve Hudson (“The Wire”) and Christian Rozakis, a stage actor who worked as a stunt player and stage combatant at The Metropolitan Opera. If “Haunted” has a happy ending — at the box office, that is — Ennis plans to return to Portsmouth to shoot a full-length feature in 2016 about two competing historic ghost walking tours. “I’ve been on a ton of them and I always thought it would be a fun, quirky thing to write about,” she said.