The first book in the Evolution series, By G M Sherwin & Sally L Roberts.

The first dawn of humanity's evolution has begun and a war is coming. 
Twenty years ago a plan was conceived of and set in motion by a group of powerful individuals. Their aim is unknown, but the outcome will soon be realised and the fate of mankind rests on the few. 
Sam and Karl meet on the morning all hell breaks loose and are set on a course that will change their lives irrevocably and hidden secrets will be revealed, can Sam figure out the changes within herself before it's too late?
 

Evolution is a killer....