Okay, so books based on TV series aren't always that great, but so far all the 24 Declassified books I've read have been gripping thrillers with plenty of action. I do wonder though, whether this might be one of the cases where the TV series is better than the books... Usually I'm a huge fan of books, even if they didn't come first (provided they're well written). However, I think something is lost from the fact that on the TV series it's one show per hour, whereas in the book it's one chapter per hour and, quite frankly, I reckon you can fit more into one hour of TV than one chapter of book. But having never actually seen the TV series, I'm not in the best position to judge that.
It's well written, it's got plenty of action. The characters are reasonably well developed, although with the exception of Jack Bauer, not brilliantly so. I certainly enjoyed reading it, and I'm keeping my eye out for the others (although they all seem to have been done by different authors so it's not all that easy to find them in the library). I think there's a case here for putting books from the same series but by different authors together.
An enjoyable thriller. Plenty of action, a pretty decent plot, and... plenty of action.