It’s been a busy time for screenwriter-director-novelist Charlie Kaufman. That last part – novelist – is his most recent designation; his first book, “Antkind,” was published in July. And now his newest film, an adaptation of Iain Reid’s creepy 2016 novel “I’m Thinking of Ending Things,” is about to premier on Netflix.

Kaufman initially made his name as a screenwriter, earning Oscar nominations for “Being John Malkovich” and “Adaptation.”, and winning the gold statue for “Eternal Sunshine of the Spotless Mind.” He donned writer and director hats for “Synecdoche, New York,” and wrote and co-directed (with Duke Johnson) the stop-motion animated film “Anomalisa.”

Very light on plot, and making use of a great deal of one character’s inner conversations with herself, “I’m Thinking About Ending Things” is about a new couple (Jesse Plemons and Jessie Buckley) – he’s Jake, we’re never really sure of her name – going to visit his parents at their isolated farmhouse. There’s a lot of small talk for the sake of talking on the way, some disturbing events when they get there, and turmoil – some of it with a musical assist – on the way back. Kaufman, 61, spoke about the film by phone from New York.

Q: Why adapt a book rather than write an original screenplay?
A: I wasn’t able to get my own stuff made. It seems to be the way that world works now, that they like preexisting properties. I found Iain’s book when I was looking for something to see if I could get a directing job. I liked the book, and thought there was some interesting stuff in there – challenging stuff for me to do, in terms of a movie. I liked the idea that it was claustrophobic and it took place in a car. So, I spoke to Anthony Bregman, a producer I work with. He has a deal with Netflix. So, they read the book, then he and I went and talked with them, and they agreed to make it. Then I wrote the script.

Q: What was your process for adapting?
A: It’s kind of a holistic approach for me. When I read the book and liked it and thought it would be a cool movie, I was just reading it casually. But then, when I have to write the script – and this is true of anything that I’ve adapted – you start to realize, “I don’t know how to do this. This is a problem. I don’t understand this. I don’t know what this character is doing here.” But I had access to Iain, so he and I had conversations about it. Then I decided that I have to make the movie that makes sense to me, using this source material.

Q: There are a lot of similarities between the book and the film, but you seem to have added a lot to the female protagonist.
A: I wanted to give the character of the young woman more agency than I felt like she had in the book. I thought it was important for me to have the basis of this weird relationship between the two of them be something that’s understandable in terms of human dynamics. Because I felt that would be more compelling in a movie, but also because I’m working with actors, and I have to give them something to do. When I figured out what that would be, the rest of the story kind of falls into place.

Q: There’s a great scene in the car where the couple is discussing John Cassavetes’ “A Woman Under the Influence,” and everything she says is a word-for-word recreation of Pauline Kael’s review of the film. Was Jessie doing an imitation of Kael’s voice?
A: No. That’s funny because we didn’t even talk about that before we shot the scene. It wasn’t like I told her to do that voice. She just came out with it, and I thought it was amazing. From what I’ve heard, I don’t think she sounds at all like Pauline Kael. But she sounds like what you’d imagine Pauline Kael to sound like, which, as far as I’m concerned, is better.

Q: There’s a point, late in your film, where you introduce the musical “Oklahoma!” What’s your history with that play?
A: I was in a stage production of it at the Hartford Y when I was in junior high school. I really like that musical, and I felt that the themes in it kind of parallel some of the struggles that Jake is having in this movie. I needed a musical for the stuff that takes place in the high school, I wanted to have a rehearsal of a musical there, and “Oklahoma!” was the one I chose. We had to fight to get the Rodgers and Hammerstein estates to let us use it, but eventually they agreed to it, for which we are very grateful.

Q: There’s a lot of fooling around with time and space in the film, and some amazing moments with Jake’s parents appearing at different ages. The most moving one has David Thewlis, as his father, suffering from dementia. What went into making that scene?
A: We rehearsed it maybe a week before we shot it. We went up to that room where it takes place, and David and Jessie did the scene. And when we were done, it was like, “OK, there’s nothing else to do here. This is perfect.” But later, when he had the prosthetic makeup on, and somehow made himself – and I don’t know exactly how he did this – but he made himself frail … it was weird! Because David is not a frail person. But he looked and acted so frail. It was beautiful. It’s really a beautiful moment in the movie. It’s funny and it’s sad and it’s horrifying.

Q: That sums up a lot of your movies, doesn’t it?
A: Yeah (laughs). I hope so. That’s what I go for.

“I’m Thinking of Ending Things” premieres on Netflix on Sept. 4.
Ed Symkus can be reached at esymkus@rcn.com.