“It is like having a child in the sense that it’s so difficult and time-consuming and it wreaks havoc on your family life,” Tim Disney tells me about making a film, just after putting his latest “William,” up on its feet, ready to walk. “[So you think] no one who has a child should ever want a child again – like who would do that again? But now I want to make another one.”

These are heartening words from the filmmaker who last directed the 2008 drama “American Violet,” but someone who had to think a lot about parenting in general to make “William,” the story of two scientists who make a personal and professional breakthrough when they conceive of a child using Neanderthal DNA to see how the ancient species would fare in the present day. Believing that perhaps their lack of critical thought doomed Neanderthals initially but their sincerity and unassuming nature could be an asset in a world where irony and cynicism reign supreme, professors Julian Reed (Waleed Zuaiter) and Barbara Sullivan (Maria Dizzia) start out with the best of intentions in bringing William into the world, against the wishes of the rest of the faculty at their academic home of Wallace University, but gradually take on different attitudes towards their son (played at his oldest by Will Brittain).

While Dr. Reed continues to view the boy, whose pronounced facial features and slower cognition separate him from his peers, as a science experiment, and Dr. Sullivan’s maternal instincts kick in, leading her to be protective of her son, William grows increasingly self-aware and Disney extends this consciousness to the audience as the young man leads those around him to contemplate what can be gained from stripping away the complexities of modern thought to see what’s right in front of them. With the film set in the Pacific Northwest where modern architectural design coexists so harmoniously with nature, you wonder whether the same could be true for William as his earnestness proves to be an uneasy fit for these times and within the small-scale tale, Disney considers the tantalizing “what if?” of the kind of culture we would have if homosapiens hadn’t come to rule the earth, but another species entirely. As “William” begins to roll out to theaters around the country, the writer/director spoke about the origins of the project, filming in Vancouver and constructing a coherent performance from multiple actors playing the titular character at various ages.

Will Brittain in "William"How did this come about?

I’m kind of an obsessive reader and I read a lot of nonfiction, so I was wasting a whole lot of time reading about the emergence of early humans and I was really taken by how unlikely our existence as a species is. We were not fated to become what we have become on earth. It could’ve worked very differently for us and we coexisted with other human species, at least three other human species, of which Neanderthals are very far the best known. By the time homosapiens co-existed with Neanderthals, which occurred for tens of thousands of years, they were our cultural equivalents. They created symbolic objects, they had complex language, and they did all of the things we associate with human behavior. They were our equals. And usually in those discussions, there’s some pretty generic assertions that homosapiens survived because of some kind of superior cultural quality or superior intelligence — a unique creative brain or whatever it is — and I got a little annoyed with that. I thought whatever history is being written by the living and prehistory too, now. So I just had the idea of what if the Neanderthals died off because they were better than us? What if they were more virtuous than us? My co-writer [J.T. Allen] and I took that idea and started developing that into a personal story.

When you have a big idea like this, is it easy to figure out the smaller scale to fit it into?

No. [laughs] The science is interesting and it kept asking for a bigger story, but I’m a guy who makes a movie every now and then and I want to do something that I really feel deeply about. I don’t know how to make a big movie and I don’t want to because it’s going to get taken out of my hands and once you get into those realms. It’s lots of other people’s money and more is at stake and then you have to get a bigger audience because you’ve spent so much money on it, and that dictates what kind of story you can tell. I thought we could tell a richer story by keeping it small.

Waleed Zuaiter and Maria Dizzia in "William"Since it has been a decade since “American Violet,” did you feel there was any difference in making a film between now and then?

The process is the same. The cameras are so much better. The lighting package you need is so much smaller. I’m someone who has no sentimentality for film. The digital world is so much more flexible and adaptable and it really, really pays off. We use the camera that has the 8K sensor on it and that gives you so much bandwidth for repositioning things within the frame because so many times in editing, it’s tiny things that mess you up – little movements or something in the corner of the frame where [you think] “This is the right shot, we really want to use that, but it’s got this little thing.” With the fidelity of the cameras and the ability to reposition from within, it gives you so much more flexibility.

And you hired these twin cinematographers Graham and Nelson Talbot, which is unusual for what’s usually an individual position. How did that come about?

We did the job in Vancouver because you get tax credit benefits and it was a beautiful place to do it, so we were going to hire somebody local. But I didn’t know anybody there, so our local production partners, who were great, had a bunch of people for me to meet. These guys at the time were 28 years old, so they were relatively inexperienced and part of me wanted to choose people with bigger resumes just to be safe, but there was something about them and it was just fantastic. It was literally like double – double quality, double work – because they’re so in tune with each other. One of them would be lighting and one would be operating or they could both be doing lighting at the same time. When we had two cameras operating, they could each operate and they did a fantastic job. And they had worked in that forest before, so that was their location suggestion.

In the Pacific Northwest, you’ve also got modern architecture amidst these naturally verdant landscapes, which nicely compliments the themes of the film. Was that also part of the appeal?

Yeah, the environment there is just so beautiful, and sometimes people go to Vancouver and they play it as something else, but we thought we’re here, we have to play it for what it is. It has this primal, misty forest idea that resonates with neanderthals and then for William, we always tried as much as possible to see him through glass, to be at a remove from him – he’s observed, he’s an object of study. Production-wise, that’s a challenge [with] reflections, but we had a great production designer.

Maria Dizzia in "William"What was it like figuring out the intelligence of William? That scene where he has trouble comprehending metaphors in particular must’ve been hard to write.

It was really the hardest thing about writing the script. We knew that he needed to be cognitively different, but how do I, with a normal human brain, conceive of someone who thinks differently? How do I think about thinking differently? It’s an oxymoron. So my co-writer and I decided not to make any decisions about that and [thought] let’s just make it nothing for a while, almost like a Chauncey Gardiner character and we’ll figure it out as we go. And that’s what happened. We started with nothing and then we liked how he’s not a gadfly. He’s not someone who says needless things.

Then we finally got to the idea of the metaphor, the indirect thinking, [and] how he understands what that is, but he doesn’t value it. It feels offensive to him in a way. He’s a more honest person than us. This was the idea that he’s more virtuous than us. He calls things for what they are. He doesn’t do all the misdirection that we all do, even in our own thinking. We’re always making up stories to justify why I forgot to bring milk home for dinner when I was asked to an hour ago. Why I forgot somebody’s birthday. I’ve always got a story. He just doesn’t do that.

Will Brittain and Maria Dizzia in "William"Is it difficult to figure out a performance that has to exist between a whole range of actors playing the same character?

Yeah, playing with all the different kids was challenging — to find kids that were similar enough in appearance. There was adult William, Will Brittain, and a toddler who was 18 months old and then a two-and-a-half year-old, a five-year-old and a 10-year-old, so we had all those different ages. The two youngest were brothers, so that helped, but the other kids were unrelated and we just looked and looked and looked. We had a great casting director, but it was hard.

Then the makeup was the biggest concern for us because we didn’t want it to become “Encino Man.” It had to be really plausible and I discovered this gentleman Stephen Bettles, who just figured it out. He has a technique he uses where he creates the “appliances” as they’re called on adhesives, and the normal technique is to create the appliances on silicon or some other material and then glue them on. It’s a time-consuming process and his just stick on. He peels them off like band-aids and puts them on. It saves so much time. And then there are other issues because the color will match [the actor initially], but then the actor gets exercised and his skin changes color, but the appliances don’t change, so there are lots of subtleties to it. it was hard, but the makeup was very effective and after a couple scenes, you just accept it. In fact, I still have trouble talking to Will Brittain without the makeup on because I just think of him, like “Who is this guy?” [laughs]

“William” is now playing in Los Angeles at the Monica Film Center and in New York at the Village East Cinemas.