THR has an interview with Stephenie Meyer, Andrew Niccol, Saoirse Ronan, Diane Kruger,and Jake Abel,
THR: Stephenie is currently in the process of penning a sequel to The Host. Do you know where the story might go?
Abel: She’s a steel trap. We tried the whole time to get little bits of information out of her, and she’s locked up tight. I have no idea. And we wondered if maybe the things we created on set would influence her. She had mentioned that watching us bring it to life had given her ideas, and the things we’ve done with each character have given her ideas of where they go, and that’s really interesting, I think, for both of us to be influencing each other in this streamlined way. … There was one thing — we wanted to play guitar in the movie. We wanted Ian to play guitar. So we got a guitar and we had a piece written for me to learn, and we were ready to go, but then she was like, “Stop!” And she wouldn’t say, but I think, hopefully, music is a big part of the second book.
Niccol: I had a beautiful piece of music composed for [Jake] to play, but Stephenie says, “No, music plays a pivotal part in the next book, so can you not play?” Funny thing is, there is a chamber in the cave where you see a guitar leaning up against the wall. It’s foreshadowing for the next movie.
Meyer: Not having written it doesn’t mean you don’t know everything that’s going to happen. I have very detailed outlines, I do a lot of outlining, to the point where there’s dialogue in my outlines. The outline for this is about 50 pages long. It gets very in-depth. So I know exactly what’s going to happen. There’s a lot you can do with a science-fiction world. There’s a lot of exploration you can do, so there’s a lot of different directions.
Make sure you check out the full interview for full details!