The suspense drama focuses on a team of experts who, after a strange phenomenon is discovered, must try to thwart the possible global threats that stem from it. Dr. Molly Anne Caffrey is a government contingency analyst whose job is to devise response plans for worst-case scenarios. In a single instant, her life changes when one of those plans -- Threshold -- is activated by Deputy National Security Advisor J.T. Baylock. Armed only with her hypothetical strategy to address an unprecedented occurrence, Caffrey now finds herself thrust in the midst of a global crisis. Now, to help her investigation, Dr. Caffrey hand-picks a team of eclectic specialists to help execute her plan: Dr. Nigel Fenway, a disillusioned NASA microbiologist; Lucas Pegg, a brilliant but neurotic physicist; Arthur Ramsey, an expert in languages and mathematics who has a penchant for unpredictability, women and alcohol; and Cavennaugh, a highly trained covert operative with a mysterious past. Together, they are in a race against the clock to identify the source of the threat that could strike at any time, anywhere and to anyone.