I thought this was the first book in the series, but there was a tagline on the cover that seemed to imply it wasn't the first book after all....or at least not the first book in the universe. 
 It was okay; certainly had a novel concept of how alternate reality-hopping time travelers can wreck havoc on other timelines and how the timelines fight back, and the writing is adequate. But somehow it was not captivating enough for me to rush-read it before the due date. Don't let that stop you though; this is no doubt a decent read if the writing style suits you.