Four is the fourth book of the Divergent series, and is centered around the life of the character Four, with four sections in the book. Is that enough four's for you? Just like the other three books, Four is written by Veronica Roth.
The first of the four sections in this book is titled "The Transfer". It gives a bit of background information of Four's life, most of which you should already know if you've read Divergent, and starts off the initiation process for the Dauntless faction. I think that the initiation will have all of the same tasks as Tris's initiation did, but in a slightly different order. Throughout the whole trilogy before this spin-off, I had wondered what Four's name was throughout the initiation process, but now I can finally sleep at night because I have figured it out.
One of the parts of the initiation for Dauntless is called the fear landscape, where you have to face all of your fears. In Divergent, this landscape was the last part of the initiation, but in Four, it is the first. Most people have fears that are in the teen numbers, but not Four. Four had four fears, which is how he got his name. Because he was named during initiation, I was confused on what he went by pre-fear landscape. It was his first task as a Dauntless trainee so no one really knew each other's names, and it was as if Four's real name never existed.
Veronica Roth has an amazingly captivating style, which means that I am most definitely going to continue reading this book.