I have read about 300 books in the past two years and by far my favorite was Intensity.  I have not come across another book yet that was as "unputdownable" as it.  Other authors I enjoy are Cody McFadyen, Alex Kava, Karin Slaughter, Tess Gerritsen, Lisa Gardner, Linwood Barclay, Jack Ketchum, and Michael Prescott.  Those authors aside, can anyone recommend a book or author that delivers the same punch as Intensity did?  Thanks!

I'd have to say....the feeling you described about reading "Intensity" I had for Richard Laymon's "In the Dark"...have you tried that one out yet?

No, I haven't.  Off to review it now.  Thanks!!!

I read Intensity a while back, so I don't remember it very well :(, but I read Relentless about 4 weeks ago, and it's still fresh in my mind :)  I want to read that one again so bad, I've put it on by wishlist.  BTW it's also by Koontz.

I was actually shaking while reading parts of Intensity.  It really grabbed me by the throat and would not let go.  It's the only book I've ever read with that experience.  Glad to know someone else had the same feeling about it.

Thanks Christine.  I started Relentless this morning and so far so good.  I am up to the part where Cubby and Penny were attacked with a stun gun in their bedroom.  I should be able to finish this by end of day.  It's a quick read.  Will post my thoughts on it compared to Intensity when I finish :-)

Welp, I finished it and thoroughly enjoyed it.  I simply could not put it down.  It didn't pack quite the punch for me that Intensity did, however, it certainly held my attention.  I had backed away from Koontz after the Odd Thomas series as I couldn't even finish the first.  I hope Dean will move forward with more novels of this nature in the future.  4.5 stars for this one.

I liked Intensity as well.  I read it 2 years ago and I still think about it often. 

As for your list of authors, have you read the 'Jack Daniels' Series by J.A. Konrath ? 
(If you like Tess Gerritsen, which I really do, then you will like these, if you haven't read them yet)

I loved (my favorite of his) is Velocity.  Absolutely brilliant.