"The Twelfth Imam" by Joel Rosenberg

How much do you really know about Shia Eschatology? If you are like me and know pretty much nothing, you will learn a little bit by reading this book. The main character is a CIA operative who has been given the task of gathering information concerning Iran's nuclear development operations. While all of this is going on, the Twelfth Imam (an Islamic Messiah-type figure, also known as the "Mahdi", or the "Promised One") seems to have appeared and is rallying the Muslim world together. There is much more to the story, of course, but this hefty book (480+ pages) will keep you interested until the very end.
This book is a fairly sharp departure (in my opinion) in style and substance from the "Last Jihad" series. In fact, it is very heavy on emotional drama and relationships and very low on action, at least until the last 100 pages of the book (which are the best, by the way). The story starts very slowly, weaving the lives of different characters (across different decades, in different countries) into one unified tale. If you have read "The Last Jihad," you will remember that a plane was blown up by an RPG in like the first five pages of that book. Not so in "The Twelfth Imam"; it's much more mellow.
Impressively, Rosenberg utilizes a lot of real information - including actual article snippets and transcribed conversations that really happened. I'm a big fan of "spy" stories, and this book delivers big on that front. Rosenberg also makes it a point to uplift the name of Jesus Christ, and there are several characters in the book that give their hearts to Christ. Very moving scenes, almost bringing me to tears a few times.
Great book, but "The Last Jihad" still sits at the top of my list for Joel Rosenberg.