After being away for ten years, director Jonathan Glazer returns with his first film since 2004's Birth, his followup to debut Sexy Beast in 2000. The new project is Under the Skin, a sci-fi horror half-documentary that features Scarlett Johansson playing an alien, who drives around in a van picking up random Scottish men. I sat down with Glazer in a roundtable interview to discuss his film, the importance of his star to the film's meaning, his interest in the paradox of being human, and more. Some spoilers for the film do follow.

Under the Skin opens in Chicago on April 11.

Did the more overt plot details from the book disappear gradually over different drafts of the film? Or did you know to get rid of these components immediately?

It was over drafts. The first couple of iterations of the script were more illustrative and more faithful. It's almost like I needed to see the draft to know I didn't want to make the film. And then you just begin to detach more from it, and move further and further away from it. You still have that link to it somewhere, there's still things about it which were remained obviously - her, the idea of why she's a woman, what she's doing as a woman, Scotland, mercy, the idea of escape. I think those were the pillars of the book that we took. In that regard, did you let go of the material that was closer to science-fiction once you knew how you wanted to approach it?

The further we got away from the book, the better we felt. Once you go off on your own trajectory, then you have to keep going in that direction. It was fairly early, but it was maybe halfway through the entire writing process that we got to what and how to visualize this space, how she deposited these men, or where she deposited these men, and how she deposited these men. I was never attached to the mechanics of the book.

Your films are able to be placed within a genre with a clean-cut plot synopsis, but then take off in their own direction. In that regard, how do you approach genre? Genre, I think for me anyway, is somewhere to launch from, and not feel like you are confined by the borders of genre, or what makes a genre movie. Under the Skin is a very science fiction-y film, particularly in a very interesting area. Genre is a conduit for ideas, isn't it? I like that about science fiction. But genre generally, I am not interested in making genre films. They have rules. I am not into that.

How did you discover your composer Mica Levi? What was the collaboration process like?

I hadn't heard her music before, or her band. She is the youngest resident of the London Philharmonic Orchestra at Southbank. My music producer is someone named Peter Raeburn, and I have been working with him for years, and we talk about soundtrack very closely, about what the soundtrack should be. He is a big part of how that whole process developed. For example, with Alexandre Desplat in Birth, he found Desplat for me. Mica was introduced to him by his business partner, and and I then heard some of her music.

I was looking for a voice, because we really needed the music to be any way that we could articulate. Things in the film that we couldn't do with dialogue, so as far as the atmospherics and the narrative breaks. Mica worked on the music for ten months, day-in and and day-out and we spent a lot of time together. We'd go between sound and music, and back again.

'Under the Skin' does so much to move away from science fiction tropes, but then you have that recurring seduction theme that sounds like it was from the 1950s. Was that connection intentional?

Yeah, it was quite a bit. It's quite strip club, I think. think Mica would describe it that way. It wants to have this erotic charge to it. So there needed to be something almost obvious about it, the spell; perfume is the way we talked about it, it was like her perfume. The other two music themes in the film, one is the alien music, the alien loop which was this inextricable sound like a hive, indistinguishable from one thing from another. Then the third is the kind of burgeoning love, the burgeoning consciousness, the human impulse.

There is no project like this before in Scarlett Johansson's career, despite our fascination with her. How much of that baggage did you want on screen? How do much do you see this film as discussion of our interaction with Johansson?

Well, it's a part of Scarlett Johansson being in the public eye, and being objectified as you say. It's fuel within that character. But she's fully in charge of that, as I am. It's not like it was by accident, it's not like I wasn't aware of it, and it's not like she's not aware of it. So I think the idea of using Scarlett, or rather her, deploying how she is objectified as part o this character, has obviously got this great weight to that, because it's her doing it. I think in terms of how we shot the nudity in the film, and what I explained to her is ... for instance, the scene where she looks at herself in the mirror, to my mind anyway, it is de-eroticizing her image, the camera is not excited. It's not a male gaze sequence. It's not titillation. I think if people go there to get their rocks off, they're better off going to see something else. I think she reclaims her image in her decision and bravery to do what she did. It's her body. And the character is also saying, "It's my body." The dovetail between what is happening in real life with Scarlett and this story is inextricably linked, and a part of Scarlett's power in this role, in my mind, is who she is publicly, and who she is as an actress.

Could you imagine making this film with a non-famous beautiful person?

We did. Very early in casting, our first casting thoughts were exactly that. It was like, "How can we have an alien, and how can we credibly present an actress as an alien?" It's just a contradiction in terms. You can't have a famous person, or someone who is familiar to us. But actually it then dawned on me that the alien isn't an actress, but the alien is playing the actress, and the character of the actress is played by Scarlett Johansson. It's an actress playing an actress.

In what point of the whole concept of the film did the idea of shooting on the fly with hidden cameras take place? Even though Johansson was disguised, were there any points where people did recognize her?

People did recognize her from time-to-time, but not as you would expect. It didn't occur to people that she would be up there. If you saw Angelina Jolie walking by you on certain streets in Glasgow, would you really think that was Angelina Jolie? You'd think, "That looks like Jolie," but the idea of her walking down that street is kind of unlikely.

What about news reports, or paparazzi? How did this idea of shooting like this come about?

We got away with that. We were very lucky, I think. People knew she was around, but we got away with it. The idea of shooting the way we did comes from ... I'd shot something in Toronto of a woman running. I had 57 cameras, and I hid them all so she had to run 400 meters, and I wanted to shoot in in the street. We would close the street, bring in extras, and shoot the street as people were getting on buses, walking, in and out of restaurants, reading newspapers, whatever. These cameras were all positioned so that when you were cutting something together it was real time, and life as it is. I think that was definitely a sketch for what we did with Under the Skin. And then coupled with this difficulty of "How do I make Scarlett Johansson credibly an alien?" And the methodology of shooting her was equivalent to the narrative; alien intelligence making this construction of an actress, and putting her in Scotland, and no one knowing anything about it, and just assuming she was a real woman. It was a beautiful moment of realization that one equaled the other, and then everything had to serve that. The logistics were very complex. You have to remain covert. Your sound man has an umbrella with a microphone in it, he's got his headphones on, and it looks like he is shuffling his iPod, but he's actually recording what somebody might be saying to the girl in the bus.

Were there any problems with getting permission from these individuals? Were there days where you were shooting and nothing came up as a result?

Both. Some said yeah, we don't want to be in it, and some agreed to. Some days you'd get something, and some days you didn't.

With your commercial background. Do you immerse yourself in pop culture, or let it come to you?

Earlier on, when I was younger I was more immersed in it, I was around it more. But I still, I try to keep in touch with it. I think it's important to be youthful in your approach with everything, and to feel like you're pushing, challenging, and exploring. And to do that you have to stay in touch with what's going on. But I'm not living it the way I was living in when I was 25. As you get older, and you do other things, it's not your time for that, it's somebody else's time. Your time is now what you're doing. For instance, with music videos, things might come my way. And Mica, she teaches me loads about current pop culture. I learned loads from working with her on the whole film, because she's out there doing this now.

What draws you to the types of films you make, and the cultures you consume? What are your thematic interests?

I think I like existential unease, I like things that examine the paradox of being a human being, in music, art and everything else. And film. I like when people ask questions of themselves, and then of me. I don't expect to have an answer. The question, if it's a good one, is enough to resonate. And usually the questions are better than the answers, the answers are usually untrustworthy.