"Don't come after us... remember the first thing I ever taught you - that your first duty is to stay alive." For some time now, Zack Darke has been operating solo, in total secrecy, for a shadowy government organization. When his handlers are abducted by someone with a serious personal vendetta against him, Zack has no choice but to go after them. Heading across the world to find them - into danger like he's never known - is something that, this time, he cannot do alone.