Australian Joel Edgerton has built an impressive resume as an actor—he played the squadron leader in “Zero Dark Thirty,” Tom Buchanan in “The Great Gatsby” and Ramses in Ridley Scott’s “Exodus”—but while he plays a pivotal role in “The Gift,” he’s also the writer-director of the tricky thriller, which also stars Jason Bateman and Rebecca Hall as a couple harassed by Edgerton, an old high-school classmate of Bateman’s with a score to settle. Edgerton has written feature scripts before—for “The Square” (2008), directed by his brother Nash, and “Felony” (2013), directed by Matthew Seville. But “The Gift” is the first time he’s directed one of them himself.

In a recent Dallas interview, Edgerton explained how his interests change depending on the particular skill he’s employing at the time. “It’s funny,” he remarked. “My taste as an actor is often very different from my taste as a writer. I just keep finding myself writing these thrillers—some of them are redemptive, some of them are a little bit more oppressive. There were a few murders in the first one I wrote and my brother directed called ‘The Square.’ The second one, ‘Felony,’ is very much about a man struggling with having done something wrong. But they’re all about someone doing something wrong and trying to find their way back to a more honest place.” Or, in the case of “The Gift,” he noted, trying to avoid dealing with past misdeeds. “I never wanted to make a straight-up revenge movie,” he said. “What I wanted to do was to tell a story where [a] by-chance encounter of two men…created an opportunity for [a] character…to begin a resolution from his point of view.

“Thrillers have been a big, sort of staple part of my movie diet since I went to drama school,” Edgerton noted. Before that it was all Arnold Schwarzenegger and Sylvester Stallone—action movies, martial arts movies, that’s what I grew up on—and old horror movies like ‘Friday the 13th’and revenge movies like ‘Death Wish.’ Elements of all that stuff end up in this movie, but when I got to drama school, I watched a lot of Hitchcock, and I really got educated by the ideas within those movies. I felt they all had some kind of social resonance and social context. It wasn’t just murder for the sake of murder. Along the way I was also drawn to the Coen brothers and movies like ‘Body Heat.’ I somehow responded to noirs. And there are hints in this movie to ‘The Shining’ and ‘Rosemary’s Baby.’ And there’s a little gesture toward Michael Haneke, too, who’s become a really big favorite filmmaker of mine.

“The idea that jump-started the movie,” he continued, “was: what would it be like for someone, twenty or twenty-five years after high school, to run into the person that he didn’t treat so well? The rules of engagement in high school are so dark. I described it once as kind of a watering-hole in Africa as the summer’s taking hold and the water source is getting smaller and smaller, and all [the different animals] have got to take a drink. That to me is what school is like. You’re all forced into the same area, and some are rulers and some are just trying to get by and not get eaten. It’s a particularly dangerous place, and there are kids doing evil things to one another. I knew I wanted to make the thriller version of that rather than a didactic version of it. This is definitely a cautionary tale, [but] I didn’t want to have made an essay on the wrongs of bullying.”

When asked how he shaped his script, Edgerton explained, “I definitely started writing the story from start to finish, but quite often I would start to sort of cross-check the script in reverse fashion. You really do have to look at the thing from all angles in a three-dimensional way to see how every thread affects every other thread, because this movie has such careful plotting [that] you’re always coming up against [artificial] contrivances or coincidences within the story.

“Audiences are very smart, so sometimes plotting a movie can be infuriating because you know when you’re cheating and you know when you’re not. And oftentimes the answer to make something not a cheat is to go back and examine character. By constantly flowing back between plot and character and turning [over] a scene from every angle and direction just to cross-check things, you hope that through careful writing and rewriting—and the support of other writers who read it—the thing starts to feel more and more airtight. And then the last part of the writing process is the editing [of the film]. There’s no one better than the editor to put final eyes on the writing.”

Asked about whether he had doubts about taking a major role in a film he had written and was directing himself, Edgerton said, “What allowed me to feel comfortable doing it was the fact that out of a 25-day [shooting] schedule, I was on screen for about seven of those. And I had my brother Nash, who’s directed movies before. He was there on set as a creative ‘outside eye’ for me.”

Edgerton was enthusiastic about his co-stars. “Getting Jason was like getting Steve Carell to do ‘Foxcatcher’ or Jim Carrey to do ‘Eternal Sunshine of the Spotless Mind,’ when you take these people who are really good at being funny and show the world that they’re also excellent at being serious,” he said. “It’s more surprising—let’s trust and like this guy because we already do, and then let him transform into [somebody with] a darker side.”

That returned Edgerton to his point that everything in a film has to be “completely tethered to character. I always thought it was something worth striving for not to create gimmicks for movies, but more to generate great, gripping stories out of character.”