David Raboy makes his feature debut with ‘The Giant,” which makes its world premiere in the Toronto festival’s Discovery section. Raboy wrote, directed and edited the atmospheric, suspenseful thriller that also plays with supernatural elements in a hot, humid small southern town. The movie’s journey began in 2010, when Raboy began writing the short “The Giant,” and it evolved over the decade.

Talk about the film’s journey to its feature-length incarnation.

I started writing in 2010. It took a long time for me to feel that it was in the right place.

I made a short then another short and I felt that it was a language that I was chasing that I hadn’t figured out how to fully bring to life. It took some time to get that right.

To this day I don’t know if I am fully satisfied!

That’s why I had to make the movie in the first place — because it was something that wouldn’t leave me alone.

Why did you use 35mm film?

It’s a medium that I grew up watching. I think there’s something that happens when you make a commitment to allocate those resources to something like that, which is a largely an aesthetic choice, then it reverberates through all the other departments — such as that I made a lot of sacrifices to make film happen and I think it just shows to everybody how seriously we take the film.

What about the look of the film?

On a more theoretical level, the movie is so concerned with darkness and imperceptibility and I found that there’s no medium like film that conveys that. When you’re looking at shadows and you’re on the precipice of an exposure, but you’re not quite there, there’s something about the fact that it is organic that could suggest images in a way that’s real. If you were to try to approximate this in digital we would know that we were adding synthetic elements to create that feeling, but there’s something about the way the light hits the film frame and there’s an alchemical reaction — and there’s one thing we’re always striving for is some sort of alchemy in filmmaking that doesn’t make it seem so deliberate, so synthetic. I think that there’s just a mystery to it that I find so compelling

How did you convey the sense of atmosphere, the humidity of the Southern setting that was integral to the tension of the film?

I think that in a lot of ways the film came to me as an atmosphere before it presented itself as a story. And so the atmosphere was always something that was going to keep us grounded in the mission of the film was. [Cinematographer] Eric [Yue] and I we always had to find the ghost in the scene. You could have two people talking, but what is it about the scene that is haunting these characters and that is the atmosphere. There’s something about summer nights in Georgia — I grew up in Virginia — where there’s a limit to how dark it is but you know you’re surrounded by things.

Talk about the choices you made in telling the story.

Eric and worked really hard over the last decade to cultivate a certain intuitive style that isn’t reliant on a plan because when you’re shooting in the South in the summer there are thunderstorms every hour. We probably lost 15-16 hours — an entire day of shooting — to lightning alone.

What’s up next?

I’d really like to see how people react to this before I say anything too definitively. What I make next I want it to be more thrilling, more romantic, more terrifying, more beautiful. I have an idea for something that I’m really excited about but it may take some time to bring it down to Earth.