Another Earth writer-director-producer Mike Cahill, co-writer, producer and leading lady Brit Marling and lead actor William Mapother talk to Jeremy Kay about the story of a guilt-ridden girl who pins her hopes of redemption on winning a contest to visit a mirror planet.

Another Earth inspired a standing ovation when it premiered at Sundance earlier this week [24]. Two days later it had sold to Fox Searchlight for all English-speaking territories and by the end of the week it had been announced as the recipient of the Alfred P Sloan Award for films with scientific themes.

 The story seems so simple and yet it hasn’t been done before. Where did it come from?

Cahill: It came from a simple idea, which was what would it be like to meet yourself and would you like that person, hate them, envy them or as in the case of this movie, be able to forgive them. The sci-fi element is a technique to ask these questions.

Did the direction of the script change a lot as you wrote it?

Marling: The thing that shifted the most was navigating the braid of the epic spectacle of this micro-drama. The feelings as the earth comes closer are asked in the smallness of this relationship. We talked about ideas and things that moved us.

Brit is arguably the discovery of Sundance. How did the casting come together?

Cahill: I knew Brit from Georgetown and she was the star of my short films and we were the best of friends and we co-directed this movie with Brit in it. I knew Brit was an incredible talent. William was a dream, too.

Mapother: In summer 2009 I was in New York City doing a public Shakespeare lab and asked my reps to set up some meetings. Two weeks later my manager heard about this independent project. I read the script and I hadn’t read one like it before.

How did the shoot go and how did you prepare for it?

Cahill: We shot in two major venues first in spring of 2009 and then in the winter. We shot in Connecticut and Newhaven, in my childhood home. Brit’s room in the film is my old bedroom.

Mapother: Before we started we did a week’s rehearsal at my house. We talked and experimented and rewrote and had a ball. You work out all these details and then to an extent you can play. Brit’s approach was so collaborative and responsive and permeable and I went into every scene without fear. I didn’t know where we were going to go but it felt so safe. For an actor that’s thrilling. I have to give credit also to Nick Hunter and the other producers – they let us work. To a degree you need to be in a childlike state and you need to be protected and to the producers’ credit I felt protected.

Marling: The moment William came on he was obsessed with everything being authentic so we would work these scenes over and over until we found something that was really honest.

What is Mike like as a director?

Marling: Mike has an energy about him when he works that’s kind of fearless and he’s deeply enthusiastic about the process of creating something and not worrying about the outcome. He infects everybody around him with that energy, and I think that’s in the film. It’s for me to work. You are liberated in the result and so deeply invested in the process.

Mapother: I have to give credit to Mike because as a first-time filmmaker he could have been overly deferential or tyrannical; but Mike had a sense of confidence and trust in us and he was very, very open to ideas but he creates an atmosphere in which I felt comfortable suggesting idea and trying new things.

How do you discover your voice as a first-time filmmaker?

Cahill: One has so many inspirations and things that bring joy but there are certain things I don’t see in the world that want to see, so somewhere that combined together.  My voice is constantly evolving. I like big tentpole concepts, but the films that I feel the most moved by are the independent, complex dramas that zoom in on the human condition. I am inspired by the question of why we are here. You don’t think about it really. It just comes through you.