While the thriller part of the story worked fairly well, the parallel universe part was really ill-conceived, and anyone who reads a lot of SF using such motifs will find it seriously flawed.
Okay, the idea is that parallel worlds exist, and that with effort some people can travel to ones close to their own. That's an SF cliche, and is okay if you realize that it's just a starting point for a story. The problem in this story is that the two worlds diverged thousands of years ago, and shouldn't be even CLOSE in terms of culture and development, because of WHY they diverged. The cause shown would have affected everything from population density to art to agriculture to science and technology. In the terminology of the story, most of the populations should be "uniques" in that they would not have exact counterparts on the other world.
Even ignoring that problem, the storytelling style is very rushed. This book reads very much as if the book was intended as a storyboard to pitch a movie based on this story. Fleshed out and thought through a little better, it might make a good movie, but it did not make a good graphic novel.