This is a completely fascinating and compelling novel. It is written in such a way that the key character Adam Walker tells his story coming from three different styles some immediate and some from a removed angle. A chance encounter with the deeply unsavoury but charismatic Mr. Born and his enigmatic girlfriend Margot, has resounding ramifications on his entire life. The title is very relevant as much is not visible, there are little mysteries that pique our curiosity. Adam, himself, has much conflict going on inside him. He wants to be a good, kind and moral person and to all intents and purposes he is, yet he has done things that he finds repellent as he views it from the perspective of how society will view it. A taboo. The book peels back layer upon layer. I cannot really specify points as it would ruin it for the reader. It is a book that lingers in the mind.