This is a book about the present being built on the bones of the past. The plot has Smilla uncovering a sequence of events stretching back to the second world war, and ultimately caused by something that happened much longer ago. At the same time, the novelist is uncovering, a bit at a time, the events that made Smilla into the person she is. For each of the people she meets along the way, we're given a glimpse of what made them the people they've become. It reminds me of John le Carré's thrillers, which are similarly portraits of people under pressure.
It took me a while to finish this book, but not because I didn't enjoy it; it's a dense read, not to be gulped down too quickly or when the mind is already full of other things.