This book is quite simply the origin of Vigilante.  Almost the whole book takes place between the death of his family and before he becomes the Vigilante.  The whole thing is a story is told by Adrian Chase who tells the story to Theresa Gomez and J. J. Davis.
 
Although there is very little that takes place besides the origin there are three important side stories.  Adrian thinks about becoming a judge.  Cannon and Saber make an unbelievable escape and the New York City gangs all unite under the Controller.