Mark Wilson Yeah, I suppose you could try cheating your way and starting with the 3rd book because there are some series where you could try that (I personally read the 5th book of the I Am Number Four series without reading the first 4 books and had no problem understanding the groundwork here), but I would not recommend doing so because like Rexenne said, a lot of the groundwork is set up in previous books, starting with the first. I would suggest at least starting with Infinity and working your way to this book before you actually read Infamous, provided you haven't already read this.
Cathy yes. I never read the first story but enough background information is given in each installment
Rexenne Well you could, but you would be lost because a lot of the groundwork for the story starts in Book #1. The first book is a bit painful to read in the beginning, but after chapter 3 things start to look up and became a quick read.