14

This was described as Lost set in an apartment building and I think that is apt.
Every few pages some new weird thing would happen.
Our hero notices some odd things about the layout of the apartments and eventually gets to saving the world.
I read “The Fold” first and then this instead of the other way.
I think you can start with either book and get the same number of surprises.
I enjoyed this a lot and will be reading more stuff by this author.