First, this book is a tome. It's long and loping and above all long.

Second, while plodding and downright incomprehensible at times, Purity is a masterful work. It's full of inside jokes and woven storylines.

I won't go too much into the plot, but to say this: much like the Bronte novel Shirley... much of this book is not about the title character and that's okay. It's okay because in a book of interesting and broken characters Purity is boring. She's wheat toast next to a case of delicious French pastries.

The overlapping storylines weave together a sick tale (in some ways more disturbing than Gillian Flynn) of relationships and shared cruelty and mistrust and anger and sexual dysfunction.

And that's part of what makes it masterful... the sickness of the characters is beyond the scope of normal humanity, but not vile physical cruelty. It's more subtle and insidious than that.