The Da Vinci Code question

Dan Brown
Matthew FitzSimmons

I've never really been much of a reader until I found Dan Brown's novels. After I read Da Vinci code, I couldn't stop reading his books and finished them all. That was a few years ago and until recently I didn't have another author that I enjoyed as much.

Then someone suggested Matthew Fitzsimmons. I have really enjoyed reading his books, almost as much as Dan Brown. But there's one problem. He only has four books and I've already almost finished all four. (if you've not read his books you should try them!)

Does anyone have a suggestion of an author that is similar to these two?

What I like about these authors? Mostly I like their writing style. Their chapters are relatively short. They typically maintain 2 or 3 primary story lines or arcs, jumping between each one until later in the book as they all merge together. The story lines are generally action packed or somewhat fast paced with drama. They aren't overly descriptive about scenes, or minute details, which would tend to lose my attention or make me bored. I really like that they take place in real life locations, and they describe the locations in accurate detail (like describing locations in Rome, or in Portugal).

I also like that they follow a main character. It creates somewhat of a bond with that character and a nice transition from book to book.

Any one have any suggestions? I'm going to be done with this last book (Debris Line) in a few days and have really enjoyed reading (surprisingly). It'll be a real bummer to not have a new book to pick up.

Thanks in advance for any help!
Dustin