Anytime you make a movie as an original, not part of a franchise or a remake, “It’s a minor miracle!” exclaimed Eric Bana.

He should know. Friday’s “Force of Nature: The Dry 2” is the never-expected sequel to Bana’s 2020 hit movie, an adaptation of Australian author Jane Harper’s 2016 bestselling novel “The Dry.”

“When we were making ‘The Dry’ we were aware that there was a second book with the character I was playing, Federal Agent Aaron Falk,” Bana, 55, recalled in a Zoom interview. “But we were so focused on trying to do the best version of this monstrously successful book that we weren’t thinking of anything else. And with good reason!

“I mean, it’s so hard to get original material off the ground. It’s such a battle. So to get the chance to do two of them? That is a pretty insurmountable obstacle if you take that on from the beginning.”

“Force of Nature” soon seemed almost inevitable. “We just applied the same rigor as on the first.  We weren’t going to do it just for the sake of it.”

Falk’s trajectory, Bana said, “is different this time. In the first story, he’s on his personal time getting dragged into an investigation. Whereas here, right from the very beginning, we find Falk in his natural environment as a federal detective who’s already part of an investigation.

“It’s the reverse: We start off with a professional Aaron, and then he leans back into his backstory and things that have occurred to him in the past.

“And we have these five amazing central women on a hike at the core of our story, characters that Jane Harper had written so beautifully.”

Key is the wilderness setting where the women get lost and murder ensues.

“Jane Harper does an amazing job of depicting landscape and having it as an essential character in the story.”

That meant a fidelity that made making “Force of Nature” well, a force of nature. “It was brutal logistically, in terms of gear. There were no comforts. We’re basically hiking in the morning and hiking until the sun was setting, sometimes in the dark. And it’s the middle of winter and it’s raining.

“That’s where the book is set. So that’s what we went hunting for. We were very lucky as filmmakers — we got to have access to locations that no film company has been able to shoot in before.

“So the audience gets to benefit from that and see a side of the Australian countryside that you’ve never seen before. It’s very sensitive areas. And very, very special and beautiful. We’re really were lucky to do that.”

“Force of Nature: The Dry 2” is available on streaming platforms and VOD May 10

Deborra-Lee Furness plays one of five Australian women who go on an ill-fated hiking retreat in “Force of Nature: The Dry 2.” (Courtesy of Narelle Portanier/IFC Films)