"I think The Iron Sea is the key track on the record - I guess because it doesn't have any lyrics, it's entirely about the atmosphere and the emotion that's expressed by the music. It's a very suffocating song, and it sounds very ominous. I find it really thrilling to listen to it, I really love it - it just sounds so oppressive and scary but in a slightly thrilling way(!), and that's basically what we tried to achieve with the whole record."