Dr. James Barron narrowly prevented a catastrophic interdimensional invasion in The Rift. But now he must deal with a myriad of threats as great as the one he overcame, including growing rifts in the fabric of reality, anomalous superstorms, and conspiracies that just might span worlds. And most importantly, he must find a way to save a woman he can't get out of his head, Special Agent Hannah Walker, who vanished through a portal with a treacherous genius named Linus. James soon finds himself heading security for a research effort taking place deep in the bowels of Camp David, where both Hannah and the portal she entered vanished. Because the portal left something behind: A nexus that floats like a black hole and defies all attempts to unravel its secrets. Is it a weapon? Or a passage to another dimension? Does it portend the end of humanity? Or is it the answer to James's prayers? James is running out of time to find out. Because if Hannah Walker is still alive, her fate hangs by a thread...