The link to the book is: http://www.aaroncrocco.com/books/as-darkness-ends/redbacks/
Here’s the blurb:
When a devastating global earthquake strikes, James Cole narrowly escapes the crumbling New York City skyscrapers with the help of a mysterious person. Now one of the precious few survivors, James’s goal is to get home to his wife through a locked-down Manhattan. But when an inexplicable darkness begins blanketing the city, deadly creatures appear and begin hunting any anybody they can find. With James and his companion the only ones capable of fighting, they’ll put their lives at stake once more in order to save the last of the survivors.
Also, book one: