Surprisingly intense and scary, the first installment of the Time Riders series was a pleasant surprise. The beginning was shocking and immediately got me interested in the book, and there were just enough gaps between action to build up a fair bit of tension. The characters appear weak at first but characterization is strong and builds them up until you can see right inside their thoughts, feel their fear and excitement. There was a fair amount of gore including mangled bodies and frightening mutant humans, though it is not graphically described. There are also some very good lessons that can be learnt from the book about teamwork, friendship and the idea of a 'perfect world'.
My only criticism is that I felt there could have been a bit more description in places, particularly of the rescuing at the beginning and New York itself, but other than that this book is brilliant.