Forensic geologist Em Hansen might finally be falling in love again. But just as she's getting closer to FBI agent Jack Sampler, he takes off on a mysterious assignment. When he doesn't return Em believes he's in trouble but only knows two things about where he's gone: Florida and killer dust. But what's the connection between the FBI and dust particles that move invisibly across the Atlantic? Risking her relationship, she goes to Florida, only to find out he's not the only person missing. A rogue scientist researching dust has also vanished-and all the signs point to foul play. Em gets a crash course in the science of dust and quickly learns there's more to the mystery than meets the eye. Two missing men are only the beginning in a larger plot of drug smugglers and global terrorism that threatens countless lives. Truth, like dust, is hidden to the naked eye, and Em must use all the tools of geology to look beneath the surface to find her boyfriend and prevent a depraved attack before it's too late.