Extinction Crisis

This story was extremely riveting. It kept me on the edge, wanting to know more every chapter. It's one of the few books that have made me read for more than 2 hours at a time.
I rated it 4 stars because the conclusion was lacking. The rush in discoveries and explanations at the end of the book were understandable, however, the book ended too quickly without a positive or negative note. The ending was extremely poorly written and seemed like something that was the product of a deadline that had to be met than a sorry that was being completed.
With all that said, it's still a great series worth reading. If not for the conclusion of the story, at least for the vast number of topics it covers and gives information about in a fun way.