That building, in the novel, has been drawn out onto the walls of three different houses that I renovated around Edinburgh while I was writing it. I went to sleep next to the plans, and woke up and was thinking like, “where’s the baby? Where’s the bone?” It was really creepy. I had nightmares sleeping next to the first wall for about six months.
I really needed those full walls to be able to work out what was happening in each decade – culturally, musically, politically, in fashion. I needed to know who was Prime Minister, if there had been a major world event. Those things began to define the lives of each different character.
There was one draft of the novel that was written in three parts, each three decades, and each decade was revisited three times, and each chapter was 3,333 words long. I had to create a corset that held it all in, so that if you remove it, the shape remains. By that point it was holding the stories back a bit, I was really willing to go where I had to go to make this world.